Reconstruction of Ryukyuan tone classes of Middle Japanese Class 2.4 and 2.5 nouns

3.1 Data

We exploit two types of resources for reconstructing pR tone classes, primary and secondary data. The primary data are used for the reconstruction of pR tone classes. They consist of the information regarding the tone class membership of eleven dialects, which all preserve the distinction between pR Classes B and C (Table 3). The Ashikebu and Nakasato dialects merged Classes A and B. The Ie dialect merged Classes A and C in bimoraic nouns. The Ikema dialect preserves the three-way contrast in pR, but Class A has almost completely merged with Class B for bimoraic nouns (Igarashi 2016b). The other dialects far more faithfully preserve the three-way contrast in pR. The secondary data are used to examine whether a given cognate is widely observed in Ryukyuan dialects and to confirm the correspondences in vowels and consonants between dialects. They consist of seven dialects that merged pR Classes B and C or that do not have tonal contrasts at all (Table 4).

MJ classes are based on Kindaichi (1974), which lists a total of 108 Class 2.4–2.5 nouns. The entries of his vocabulary are written in italics in the MJ forms (Akinaga et al. 1997).

Word forms are provided in broad phonetic transcription. The diacritic “′” indicates a glottalized consonant. Long vowels are represented by a series of identical vowels. “ï,” “ɨ,” and “ɿ” are uniformly written as “ɨ.” The pairs “ʃ” and “ɕ” and “ʒ” and “ʑ” are uniformly represented as “ɕ” and “ʑ,” respectively. Moreover, the diacritics “^┌” and “^┐” designate a pitch rise and fall, respectively. For example, “μ^┌μ” (“μ” stands for mora) represents an LH pitch pattern (“L” and “H” stand for low and high pitch, respectively). “μ^┌μ^┐” is distinguished from “μ^┌μ”; when produced in isolation, the two are (nearly) indistinguishable, but when immediately followed by another morpheme such as a case particle, the former is realized as LH-L, whereas the latter is realized as LH-H. In Tarama and Ikema, tonal neutralization occurs with nouns produced in isolation. Tone opposition can be observed, for example, by adding one or more bimoraic particles (one for Tarama and two for Ikema) after the noun. The -kara ‘from’ and -mai ‘also’ in the tables are bimoraic particles.

A superscript at the end of each word form indicates the correspondence with the pR tone class, where “A,” “B,” and “C” are the pitch patterns corresponding to the pR Class A, Class B, and Class C, respectively. Because of the conditioned merger that occurred in each dialect, one pitch pattern may correspond to more than one class. In that case, more than one letter is used to indicate the correspondence. For example, “AC” indicates that the pitch pattern corresponds to both pR Classes A and C, and “BC” indicates that the pitch pattern corresponds to both pR Classes B and C.

Because we use multiple sources for Tarama, there can be mismatches in the pitch pattern between the sources. In case of discrepancy, the pattern in the author’s field note is adopted first, with that in Tokuyama and Celik (2020) in parentheses; for example, “^(∼A).”

3.2 Reconstruction

We postulate the phoneme inventory in Figure 1 for pR. We assume that an intervocalic *w occurred only before *a, an intervocalic *j was allowed only before a back vowel, and *d had already merged with *z before a high vowel. No obligatory glide insertion is assumed between vowels. Thus, the pR noun for “voice,” for example, is reconstructed as *koe instead of *kowe or *koje. We leave aside whether *t, *d, *s, and *z were palatalized before a high vowel. We use a capital *U in cases where we could not decide whether *o or *u was to be reconstructed. Examining the segmental correspondence between dialects is important for determining whether nouns that are similar in both meaning and form are cognate with each other. The determination of cognacy constitutes an indispensable part of the reconstruction of the pR tone class of the nouns. Furthermore, the correct reconstruction of word-final vowels in pR is crucial for testing the conditioned merger hypothesis. We discuss the issues concerning the segmental reconstruction and cognacy between nouns only if they require argumentation.

When the tonal correspondence between the dialects is irregular, we adopt the principle of parsimony, according to which the reconstruction should require the fewest sound changes. The parsimony is assessed on the basis of the phylogenetic tree proposed by Pellard (2015) (Figure 2). For example, pR *poka ‘outside’ exhibits irregular tonal correspondence (Ashikebu ɸuka ^AB, Asama ɸukaa ^B, Wadomari ɸaa ^B, Yoron huka ^C, Ie ɸuk’aa ^B, Nakijin ɸuk’aa ^B, Shuri ɸuka ^B, Tarama puka ^C, Ikema huka ^C, Yonaguni huga ^B). If we posit pR Class B, then the sporadic sound change B > C is reconstructed to occur two times, each for Yoron and proto-Miyako. By contrast, if we posit pR Class C, then the sporadic sound change C > B is reconstructed to occur five times, each for Ashikebu, Asama, Wadomari, proto-Okinawa, and Yonaguni. Thus, the principle of parsimony judges Class B as more plausible than Class C.

Figure 1

Proposed phoneme inventory in pR.

Figure 2

Phylogenetic tree of the Japonic language family proposed by Pellard (2015). The phylogenetic position of Hachijo is controversial, which is indicated by a dotted line.

4.1 Confirmation of tone classes reconstructed by previous studies

The survey confirmed that the tone classes reconstructed by previous studies were valid for 52 of the 55 words (Table 5). In the table, nouns that show an irregular tonal correspondence are shaded. In addition, segments that obviously show an irregular correspondence are underlined. The exceptional correspondence exhibited by quite a few dialects in nouns where cognates are found in most dialects can be regarded as the result of sporadic changes in individual dialects and does not affect the reconstruction of tone classes based on the principle of parsimony. Sporadic changes of this sort are not discussed in this section. Some nouns require further commentary, which is provided below.

Table 5

Comparison and reconstruction of Class 2.4–2.5 nouns. Ha79, Hattori (1979a,b); Sh07, Shimabukuro (2007), Ma09, Matsumori (2009), Bo10, de Boer (2010), Ma12, Matsumori (2012)

13. *sora C ‘treetop’: Matsumori (2009, 2012) also reconstructs Class C for *sora ‘treetop,’ although she may not agree with the view that pR *sora C ‘treetop’ is related to MJ sora 2.4 ‘sky.’ In the tenth century, Japanese sora referring to not only ‘sky’ but also ‘the upper part of an object (such as roof, ceiling, and treetop)’ is attested (NKDJ 2001, 507). This means that at the stage of MJ at the latest, Japanese sora also had a meaning equivalent to that of pR. This study does not examine the question of whether the pJ cognate had the meaning of ‘the upper part of an object.’ What is clear from the above discussion is that the semantic change between ‘sky’ and ‘the upper part of an object’ is a natural process, and that pR *sora ‘treetop’ is reasonably regarded as the cognate of MJ sora 2.4 ‘sky.’ Note that pR *sora does not have a meaning ‘sky,’ which is indicated instead by a Chinese loan pR *ten A.

21. *moko C ‘bridegroom’: Nakasato, Asama, and Yoron have mukk’a ^C ‘bridegroom,’ mukk’wa ‘id.,’ and muukwaa ^C ‘id.,’ respectively. They must be polymorphemic, consisting of pR *moko C ‘bridegroom’ and pR *kua A ‘child,’ or they arose through reanalysis of the second syllable of pR *moko C ‘bridegroom’ as pR *kua A ‘child.’ The regular tonal correspondence allow reconstruction of pR *moko C ‘bridegroom.’

25. *tuju C ‘dew’: Whether the pR form of ‘dew’ is *tuju or *tujo becomes clear when comparing ‘dew’ with pR *tujo- ‘strong’ in Ishigaki and Hatoma, Ishigaki tɕuu ^BC ‘dew’ and tsuu- ‘strong,’ and Hatoma ɕuu ^BC ‘dew’ and suu- ‘strong.’ They are distinguished by the palatalization of the consonant. For this, pR *tuju ‘dew’ is reconstructed. Tarama tsɨv ^C ‘dew’ may not seem to be a reflex of pR *tuju ‘id.’ However, the sound change pR *ju > v is confirmed by pR *suju- ‘sour,’ reflected in Tarama sɨv- ‘id.’^[6] In Irabu, pR *tuju ‘dew’ and *suju- ‘sour’ are also reflected as tsɨv and sɨv-. Thus, the change pR *ju > v/*{s, t}u_ can be reconstructed in proto-Miyako.^[7]

26. *woke C ‘bucket’: The correspondence of the word-initial consonant is irregular in Nakijin, Tarama, and Yonaguni, suggesting that sporadic sound changes occurred in these dialects. These changes, though irregular, are phonetically motivated at least for Nakijin and Tarama; in Nakijin, w became ɸ by assimilating its voicing to that of the consonant in the following syllable, and in Tarama, *b (<*w through a regular sound change) became ɡ by assimilating its place of articulation to the consonant in the following syllable. The tonal correspondences are regular throughout all dialects. These facts indicate that these nouns are inherited from pR, allowing us to reconstruct pR *woke C ‘bucket.’

32. *kama B ‘sickle’: Although Matsumori (2012) reconstructs Class B, only Amami exhibits pitch patterns corresponding to pR Class B according to our survey. The pitch patterns in Okinawa, in contrast, correspond to Class A. The cognates are perhaps absent in Southern Ryukyuan, where reflexes of pR *irana C ‘sickle’ are attested instead (Tarama ɨzara ^C, Ikema zzara ^C, Ishigaki ʔiɾana ^BC, Yonaguni irara ^C). They are also attested in Okinawa (Nakijin ʔinaana ^C, Shuri ʔirana ^C). Regardless of whether the pR Class of *kama is reconstructed as A or B, the number of reconstructed changes remains the same: the change A > B in proto-Amami or the change B > A in proto-Okinawa. Because Class B or C is a regular correspondence with MJ Class 2.4, it is more plausible to reconstruct pR Class B for *kama ‘sickle’ and a subsequent sporadic change B > A in proto-Okinawa.

36. *kinu B ‘garment’: The noun listed as a Class 2.4 noun in Kindaichi (1974) is not kinu ‘garment’ but kinu ‘silk.’ They both are also attested in OJ, the oldest attested stage of Japanese, and are generally recognized as cognates (Jodaigo 1967, Martin 1987). Their pitch patterns are both LH in MJ (Akinaga et al. 1997), a regular reflex of Class 2.4 in MJ. Additionally, there are modern Japanese dialects with kinu ‘garment’ also corresponding to Class 2.4 (Hirayama et al. eds. 1992–93). Reflexes of pR *kinu B ‘garment’ are observed throughout Ryukyu Islands. However, only a few dialects have nouns for ‘silk,’ in which the tonal and segmental correspondence is irregular (cf. Yamatohama k’iɴ ‘garment’ vs k’iɴ ‘garment’; Asama kiɴ ^BC ‘garment’ vs k’inuu ^A ‘silk’; Yoron kiɴ ^B ‘garment’ vs kinu ^B ‘silk’). It is suggested, therefore, that pR *kinu B lacked the meaning ‘silk’ and that apparently related Ryukyuan forms for ‘silk’ are Japanese loans. In any case, the fact that MJ and some Japanese dialects have kinu ‘garment’ belonging to Class 2.4 indicates that, regardless of whether ‘garment’ and ‘silk’ are cognates, the tone class of pR *kinu ‘garment’ is 2.4b.

38. *miso B ‘bean paste’: Matsumori (2012) reconstructs Class B. Tonal correspondence is regular between the dialects of Northern Ryukyuan but irregular between the dialects of Southern Ryukyuan. The former suggests that the pR Class of *miso is Class B, whereas the latter suggests it can be Class A, B, or C. The irregular tonal correspondence may suggest that borrowing is involved in this noun. However, the segmental correspondence is perfectly regular, which decreases the plausibility of the borrowing hypothesis. We, therefore, assume that the reflexes are inherited from pR, and the irregularity in the tonal correspondence is due to sporadic changes independently occurring in each dialect. Because Class B requires the minimal number of sound changes, we reconstruct Class B for pR *miso.

42. *soto B ‘outside’: Hattori (1979a,b) reconstructs Class B. In our primary data, reflexes of pR *soto exhibit a limited distribution. Hattori (1979a,b) reveals that its reflexes are observed in many dialects of Amami (in addition to Asama ɕutuu ^B, Kametsu ɕutu ^B, Shodon sɨt’uu ^BC, Naze sutʰu ^B, Aden sut’u ^B, and Onotsu sut’u ^BC). Because the tonal correspondences between dialects are regular and the reflexes are observed both in Amami and Okinawa, we assume that they were inherited from pR *soto ‘outside.’ The lack of its attestation in Southern Ryukyuan may be because its reflexes were replaced by almost synonymous pR *poka B ‘outside.’

49. *mado B ‘spare time’: Matsumori (2009, 2012) also reconstructs Class B for *mado ‘spare time,’ although she may not agree with the view that pR *mado ‘spare time’ is related to MJ Class 2.4 MJ mado ‘window.’ We postulate a metaphoric semantic change ‘window’ > ‘spare time,’ that is, the change from ‘special gap’ to ‘temporal gap.’ This type of change is also observed in other languages such as Russian (cf. oкнo ‘window,’ oкнo мeждy лeкциями ‘spare time between lectures’) (Morkovkin et al. [eds.] 2016, 678). The nouns for ‘window’ per se are scarcely attested in Ryukyuan. Even if they are, they tend to be unrelated to MJ mado 2.5, as in Shuri haɕiɾu ^BC ‘sliding window,’ takabaɕiɾu ^BC ‘high window,’ and Ishigaki takaɸusaɾa ^BC ‘high window.’ It is true that Taketomi and Yonaguni have mədu ‘window’ and Yonaguni madu ^B ‘window,’ respectively, but they may be a Japanese loan. The Yonaguni madu ^B ‘window’ recorded by Uwano (2013) is especially controversial, because, as pointed out by the author, the same speaker produces amadu ^A ‘window’ instead of madu ^B, as described in an earlier study (Uwano 2010). Thus, a plausible scenario is that at the stage of pR, *mado lost its original meaning of ‘window,’ whereas the form *mado itself survived with its meaning metaphorically changed from ‘window’ to ‘spare time.’

50. *majo B ‘eyebrow’: Although Martin (1987) regards MJ maju 2.5 ‘eyebrow’ and maju 2.5 ‘cocoon’ as cognates, they are listed as separate entries in the present study. Although the evidence for a distinction between pR *ju and *jo is in general scarce in modern Ryukyuan dialects (Pellard 2023), we reconstruct pR *majo, not *maju, based on the following evidence.^[8] The final syllable of pR *majo B ‘eyebrow’ is reflected differently from that of pR *kaju A ‘porridge’ in many Ryukyuan dialects (Ashikebu majo ^AB ‘eyebrow’ vs kai ^AB ‘porridge’; Shuri maju ^B ‘eyebrow’ vs kee ^A ‘porridge’; Hatoma maju ‘eyebrow’ vs kai ‘porridge’; Ishigaki majoo ^BC ‘eyebrow’ vs kai ^A ‘porridge’). Although it still seems possible to reconstruct pR *kai, not *kaju, for ‘porridge,’ this hypothesis is rejected because the second syllable of pR *kaju ‘porridge’ yields different forms from that of pR *mai A ‘rice’ in at least two Yaeyama dialects, namely, Hateruma (kee ‘porridge’ vs mëë ‘rice’) and Aragusuku (kai ‘porridge’ vs majɨ ‘rice’). The correspondence with MJ kaju 2.1 ‘porridge’ also provides an additional support for the reconstruction of pR *kaju A ‘porridge.’

4.2 Nouns for which the pR class was newly reconstructed (23 words)

We newly reconstructed the pR tone classes of 23 nouns (Table 6). The majority of these nouns are attested in both Northern and Southern Ryukyuan, and their tonal correspondences are highly regular, but their pR tone classes have not been reconstructed in previous studies.

Table 6

Newly reconstructed Class 2.4a/2.5a and Class 2.4b/2.5b nouns

56. *kesa C ‘a short while ago’: We postulate a semantic change ‘this morning’ > ‘a short while ago’ following the NKDJ’s (2001, 1321) view. The Niigata dialect of Japanese also has kesa ‘a short while ago’ (Ohashi 2003, 90), suggesting that this type of semantic change is natural. Northern Ryukyuan forms exhibit an unexpected geminate, which requires further research.

58. *nau C ‘what’: For the reconstruction of *nau, not *nao, see Jarosz (2019).

59. *tubu C ‘grain’: Widespread Ryukyuan nouns for ‘grain’ are the reflexes of pR *tuzu C ‘grain’ (Yoron tɕiʑi ^C ‘id.,’ Ie sidzi ^AC ‘id.,’ Ishigaki tsɨdzɨ ^BC ‘id.,’ Yonaguni tɕ’iɴ ^C ). Evidence for *tubu ‘grain’ is sparse in the primary data, but in the secondary data, we find Yamatohama tz’ɨbu ‘grain,’ Taketomi subu ‘id.,’ and Ishigaki subu ^BC ‘grain.’ Tarama tsɨv ^C ‘dew’ discussed in Section 4.1 may at first glance seem to be a reflex of pR *tubu C ‘grain’; the difference in meaning between ‘grain’ and ‘dew’ appears to be the result of a contamination with pR *tuju C ‘dew.’ However, evidence shows that, although pR *bu is spirantized into v(u) in many environments in varieties of Miyako, including Tarama (cf. pR *kobu C ‘spider’ > Tarama kuvu ^C ‘id.,’ pR *abura B ‘oil’ > Tarama avva ^B ‘id.’), the spirantization does not occur when *bu is preceded by *tu. For example, in pR *tubusi A ‘knee’ (Yoron tɕinɕi ^A ‘id.,’ Nakijin tʑ’inɕi ^A ‘id.,’ Ishigaki tsɨbusɨ ^A ‘id.’) and pR *tuburu C ‘head, calabash’ (Yoron tɕibuɾu ^C ‘head,’ Nakijin tʑ’imbu ^C ‘id.,’ Ishigaki tsɨburɨ ^BC ‘id.’), *bu is not spirantized in Tarama as in tsɨbusɨ ^A ‘knee’ and tsɨbuɭ ^C ‘calabash.’ In other varieties of Miyako, *bu in these nouns is reflected as ɡu (Irabu tsɨɡʊsɨ ‘knee,’ tsɨɡʊɨ ‘calabash’; Ikema sɨɡusɨ ^A ‘knee,’ tsɨɡui ^C ‘calabash’) (Celik 2020), likely through sporadic change^[9]. Therefore, Tarama tsɨv ^C ‘dew’ is not a reflex of pR *tubu C ‘grain.’ This evidence also indicates that Ikema tubu ^C ‘grain’ is a regular reflex of pR *tubu C ‘id.’

61. *tuti C ‘hammer’: In the primary data, its reflexes are only attested in four dialects of North Ryukyuan, but in the secondary data, they are also attested in Southern Ryukyuan (Ishigaki tsɨtsɨ ^BC ‘hammer’). Therefore, it is safe to assume that this noun exists in pR.

71. *puna B ‘gibel’: As far as the data in Table 6 are concerned, the principle of parsimony cannot determine whether the tone class of pR *puna ‘gibel’ is B or C. The cognates of pR *puna are infrequent in Ryukyuan dialects. However, in Uwano (1998) study on many varieties in Okinoerabu Island, 24 of the 35 varieties have the cognates of pR *puna, and in all but one of the 24 varieties, the pitch pattern corresponds to Class B. Based on this, we reconstruct pR *puna B ‘gibel.’ The segmental correspondence in the first syllable in Yonaguni huna is irregular (compare pR *puna ‘gibel’ with pR *pune C ‘boat’ [Yonaguni nni ^C, Yoron puni ^C, Shuri ɸuɲi ^B] and with pR *pugori A ‘testicles’ [Yonaguni ŋɡui ^A, Yoron pugui ^A, Shuri ɸuɡui ^A]). It is therefore possible that borrowing is involved in this noun for Yonaguni. If Yonaguni huna ^C corresponding to Class C is a loanword, then the view that the tone class of pR *puna ‘gibel’ is B becomes more plausible.

73. *koto B ‘zither’: The segmental correspondences are irregular, suggesting that borrowing is involved. The correspondence between MJ and Southern Ryukyuan suggests that the first syllable in pR is *ko. Although pR *ko reflects as ɸu in Ie and Nakijin, the first syllable in ‘zither’ is kʰu in both dialects. The Shuri form has an unexpected long vowel in the second syllable. The Asama form has an unexpected vowel o, and the speaker is aware that this is a new word (Uwano 2017a, 152). However, the regularity of tonal correspondence (except Yonaguni) and the widespread attestation make us hesitant to deny the existence of this noun in pR.

74. *majo B ‘cocoon’: It is more difficult to determine whether the final syllable of ‘eyebrow’ is *ju or *jo than in the case of pR *majo B ‘eyebrow.’ Ashikebu distinguishes between majo ^AB ‘eyebrow’ and mai ^AB ‘cocoon’ and the final vowel of the latter agrees with that of kai ^AB ‘porridge’ (<pR *kaju A ‘id.’); therefore, pR *maju ‘eyebrow’ is favored. However, Taketomi, which does not distinguish məju ^BC ‘eyebrow’ and məju ^BC ‘cocoon,’ has kəi ^A ‘porridge’ with a different vowel from that in ‘eyebrow’ and ‘cocoon,’ supporting pR *majo B ‘cocoon.’ Although the conflicting sound correspondences are difficult to interpret, we reconstruct pR *majo B ‘cocoon’ first, because both ‘eyebrow’ and ‘cocoon’ are majo ₁ in OJ, and second, because there is a theory (Martin 1987, 474) that views these two nouns as cognates.

4.3 Class 2.4–2.5 nouns whose pR classes remain unsettled

The pR tone classes of the 17 nouns shown in Table 7 remain unsettled primarily because of irregular correspondences between Ryukyuan dialects or between pR and MJ.

Table 7

Class 2.4–2.5 nouns for which pR tone classes remain unsettled. Ha79, Hattori (1979a,b), Ma09, Matsumori (2009), Bo10, de Boer (2010)

76. *itu A? ‘when,’ 77. *sumi A? ‘inside corner,’ 78. *abo A? ‘horsefly,’ 79. *aki A? ‘autumn,’ 80. *pabu A? ‘snake,’ 81. *turo A? ‘crane’: The comparison of Ryukyuan dialects suggests that the tone class of these six nouns is Class A, which is an irregular reflex of MJ Class 2.4–2.5. At least for some of them, the irregularity may be explained by borrowing. However, the relatively regular tonal correspondences between dialects suggest that the borrowing, if any, occurred at the stage of pR. We leave open the issue regarding the irregularity and the reconstruction of tone classes of these nouns.

For *pabu A ‘snake,’ there is an additional issue about its cognacy. The irregularity of correspondence between MJ femi 2.5 ‘snake’ and pR *pabu A occurs not only in tones but also in segments. Furthermore, the cognates of pR *pabu A usually refer to a venomous snake endemic to the Ryukyu Islands, rather than to snakes in general; thus, the meanings do not exactly correspond. Therefore, instead of the view that pR *pabu A is related to MJ femi 2.5 ‘snake’ (e.g., Jarosz et al. [2022]), we should explore the possibility that pR *pabu A is related to MJ fami ‘viper.’ Cognates that may be related to MJ fami ‘viper’ are widely distributed in Kansai, Chugoku, and Shikoku Districts in the forms of hami, hame, hamu, habi, habe, habu, and so forth, all of which mean ‘viper’ (LAJ 1966–1974, Map 228). Crucially, the pitch pattern of MJ fami ‘viper’ is HL, a regular reflex of Class 2.2, which in turn regularly corresponds to pR Class A. Meanwhile, Wadomari and Shuri have nouns referring to ‘snake’ in general, namely, çibu ^C and ɸiibu ^C, respectively. Although evidence is sparse, it may be possible to reconstruct pR *pebu C ‘snake’ along with pR *pabu A ‘venomous snake.’ If this holds true, then it is pR *pebu C ‘snake’ that is related to MJ femi ‘snake,’ and its tonal subclass is Class 2.5a.

82. *aka A? ‘red,’ 83. *ao B? ‘blue,’ 84. *kuro B? ‘black,’ 85. *siro B? ‘white’: These four words are color terms, which do not appear as free nominal morphemes in Ryukyuan but are adjectives that appear with a following component. In Table 7, the adjectives followed by a noun for ‘color’ (a reflex of pR *ero B ‘color’ [Pellard 2013]) are represented. *aka ‘red’ seems to belong to pR Class A, whereas the others seem to belong to pR Class B. However, these classes are those of adjectives, not nouns. Adjectives may have different tone systems than nouns, and the pR tone system of adjectives has been little investigated. We therefore do not reconstruct the tone class of these color terms.

86. *kazu B∼C ‘number’: Although de Boer (2010) reconstructs Class C, half of the dialects in our data exhibit pitch patterns corresponding with Class B.

90. *gaki?? ‘oyster’: Hattori (1979a,b) regards pR as having a cognate whose tone class is Class B based on five Northern Ryukyuan dialects: Asama gatsɨɨtsɨ ^C ‘oyster?,’ Nakijin gatʑii ^B ‘oyster’ (gatʑ’ii ^B, Nakasone 1983), Kushi gakii ^BC ‘id.,’ Onna gaatɕi ^B ‘id.,’ and Shuri ɡatɕitɕaa ^BC ‘sea urchin.’ However, the meaning of Asama gatsɨɨtsɨ ^C is not ‘oyster’ but ‘urchin’ according to Uwano (2017a, 157), and the meaning of Shuri ɡatɕitɕaa ^BC is, as Hattori (1979a,b) also noticed, ‘urchin.’ In terms of segmental correspondence, too, these two nouns appear unrelated to MJ kaki 2.5 ‘oyster.’ The dialects listed in Hattori (1979a,b) that include the nouns straightforwardly related to MJ kaki are Nakijin, Kushi, and Onna. Yamatohama also has gaki ‘oyster.’ Therefore, it is possible to reconstruct pR *gaki B ‘oyster,’ although its reflexes are observed only in Northern Ryukyuan.

However, if we follow Hattori’s theory that ‘oyster’ and ‘urchin’ are related, it is necessary to compare the nouns for ‘urchin’ between dialects. They have various reflexes, such as Asama gatsɨɨtsɨ ^C, Ie ɡasisi ^AC, Nakijin ɡaɕiiɕi ^C, Shuri ɡatɕitɕaa ^BC, Tarama kadzɨtsɨ ^C, Ikema kazɨtsɨ ^C, Ishigaki kakidzɨ ^BC, and Taketomi kəkitɕi. Their tonal correspondences are perfectly regular, which allows us to reconstruct them as belonging to Class C. Irregular segmental correspondences make it difficult to reconstruct the proto-form. Assuming that variation in voicing across dialects is due to a sporadic voicing of original voiceless consonants, the proto-forms can be reconstructed as *kakisu, *kakiti, *kakesu, *kaketi, *kasesu, *kaseti, and so forth. If the proto-form for “urchin” were *kasesu or *kaseti, then it would be related not with MJ kaki ‘oyster’ but with MJ kase ‘urchin.’ By contrast, if the proto-form were *kakiti or *kakisu, then hypothetical relatedness between ‘oyster’ and ‘urchin’ becomes more plausible. In fact, Ashikebu has gak’isɨ ^B ‘oyster’ (not ‘urchin’!), which corresponds to *kakisu. The Ashikebu form would provide a support for Hattori’s (1979a,b) theory that the nouns for ‘oyster’ and ‘urchin’ are related. Noteworthy is that the pR tone class of ‘urchin’ is reconstructed as Class C based on the regular tonal correspondence between many dialects, whereas we reconstructed Class B for *gaki ‘oyster’ based on limited data of Northern Ryukyuan. If we focus on the limited distribution of *gaki, we can regard it as a loanword at later stage and reconstruct pR *kaki(-su) ‘oyster,’ whose tone class is C. The history of the pR noun for ‘oyster’ is complicated, which forces us to reserve judgment as to whether its tone class is B or C.

91. *koi?? ‘carp’: Only two dialects had a reflex of this noun in our primary data. Asama koi is irregular, as the dialect experienced a change from pR *ko to ku in word-initial position. In addition, it is a neologism according to the source. Irabu and Taketomi have kʊi and kui, respectively, although information about pitch patterns is not available. Nakijin and Shuri have polymorphemic forms, kʰuuʔjuu ^B and kuuʔiju ^BC, respectively. The second components must be a reflex of pR *io A ‘fish,’ although it is not clear whether the first component is related to MJ kofi 2.5 ‘carp.’ It is especially doubtful for Nakijin, where pR *ko changes into ɸu in a word-initial position. By contrast, Ishigaki has a more transparent form kuiʔidzu ^BC?. A relatively reliable datum for identifying the pR tone class of *koi is Tarama kui ^C; however, only one reflex is insufficient for reconstructing the tone class.

93. * asa- ? ‘morning’: Although the presence of *asa ‘morning’ in pR has been doubted (Vovin 2008, 2010), as Pellard (2017) argues, *asa- is considered to exist in pR because the cognates of MJ asa 2.5 ‘morning’ are observed in many compounds in both Northern and Southern Ryukyuan. The compounds containing pR *asa- include Yamatohama ʔasa-duɾɨ ‘morning calm’ and ʔasa-tz’ɨju ‘morning dew’; Yoron asa-ɕu ‘morning tide’; Ie ʔasa-duɾi ‘morning calm,’ asa-ɕu ‘morning tide,’ and asa-tida ‘morning sun’; Nakijin hasaa-duɾii ‘morning calm’ and hasaa-tz’iju ‘morning dew’; Shuri ʔasa-duɾi ‘morning calm’ and asa-tsiju ‘morning dew’; Tarama aɕa-duri ‘morning calm,’ aɕa-tsɿv ‘morning dew,’ and aɕa-ɕu ‘morning tide’; Hatoma ʔasa-duri ‘morning calm,’ ʔasa-pana ‘early morning,’ and ʔasa-kai ‘morning porridge’; and Ishigaki ʔasa-duri ‘morning calm’ and ʔasa-kai ‘morning porridge.’ It is unclear whether pR had a free morpheme *asa ‘morning’ because its reflexes are rarely, or not at all, used in isolation. Because the method of determining the tone class of the constituents of a compound is only established for a limited number of dialects, we do not reconstruct the tone class of the bound morpheme *asa- ‘morning.’

4.4 Class 2.4–2.5 nouns whose existence in pR is doubtful

A total of 15 MJ Class 2.4 nouns shown in Table 8 have not been reconstructed for pR, because their existence in pR is strongly doubted.

95. geta 2.4 ‘clogs’: Although we find Yamatohama gɜtʰa ‘clogs’ and Shuri dʑita ^B ‘id.,’ they must be borrowings. First, the segmental correspondence between Shuri and MJ is irregular. Second, the two dialects also have synonymous ʔaɕidʑa ‘clogs’ and ʔaɕidʑa ^BC ‘id.,’ respectively. They are reflexes of pR *asida B∼C ‘id.,’ whose reflexes are widely observed in Ryukyuan dialects.

96. iti 2.4 ‘market’: We observe only Yamatohama itʑ’i ‘market.’ The limited attestation suggests that it is a Japanese loan.

97. kai 2.4 ‘oar’: Only Shuri has a form, kee ^BC ‘oar,’ that may be related to MJ kai 2.4 ‘oar.’ However, Shuri also has a synonymous ʔjeeku ^C ‘oar,’ which is a reflex of pR *ijako B∼C ‘oar.’ The reflexes of *ijako are observed throughout Ryukyu Islands (Yoron jahu ^B, Ie ʔjaaɸu ^AC, Nakijin jaɸuu ^B, Tarama ɨzaku ^C, Ikema zzaku ^B, Yonaguni daŋŋu ^B). Shuri kee ^BC ‘oar’ can therefore be regarded as a borrowing.

99. kiri 2.4 ‘awl’: We observe Yoron ii ^B ‘awl,’ Nakijin ʔiɾii ^B ‘id.,’ Tarama iɭ ^B ‘id.,’ Yonaguni iri ^B ‘id.,’ and so forth, which allow the reconstruction of pR *iri B ‘awl.’ Although pR *iri B ‘awl’ at first glance seems related to MJ kiri 2.4 ‘id.,’ the resemblance must be superficial. Based on Igarashi (2021), we assume that pR *iri B ‘awl’ is instead related to a verb igir- ‘to make a hole with an awl’ observed in modern Japanese dialects spoken in Kyushu. Igarashi’s (2021) hypothesis is motivated by a geographical distribution of various nouns for ‘awl’ in Kyushu. Japanese dialects spoken in Kagoshima and Miyazaki Prefectures have reflexes of *iri, not *kiri (NHDJ 1989, 195, Hashiguchi 2004, 138–39, 211). In addition, reflexes of *igiri ‘awl’ are observed in dialects spoken in Izumi and Akune, the northernmost cities in Kagoshima Prefecture, as well as dialects in Kumamoto and Nagasaki Prefectures, located north of Kagoshima Prefecture (NHDJ 1989, 155, Hashiguchi 2004, 148). Because *iri and *igiri complement one another geographically and their meanings coincide, they must be cognate. The former must have developed from the latter though an irregular sound change that drops the intervocalic *g. Notably, a verb igir- ‘to make a hole with an awl’ is attested in dialects spoken in Kumamoto, Nagasaki, Saga, and Fukuoka Prefectures (NHDJ 1989, 155). This region completely covers the places where reflexes of *igiri are attested, suggesting that *igiri is a gerund of a verb *igir-. These observations lead us to assume that pR*iri is related to *iri, *igiri, and *igir-, but not to MJ kiri ‘awl.’ The irregular dropping of the intervocalic *g in *igiri is considered as a shared innovation between Ryukyuan and Japanese dialects in south Kyushu.

100. titi 2.4 ‘milk’: Yoron tɕiitɕii ^C ‘milk,’ Nakijin tʑ’iitʑ’ii ^C, and Shuri tɕiitɕii ^BC seems related to titi 2.4 ‘milk.’ However, they all are nursery words. The pR form for ‘milk’ is *tii B (cf. Ie tɕ’ii ^B, Nakijin tʑ’ii ^B, Shuri tɕii ^B, Tarama tsɨɨ ^B, Ikema tsɨɨ ^B). The three nursery words must be a reduplication of pR *tii B ‘milk’ that developed independently in each dialect.

102. tuba 2.4 ‘sword guard’: We observe only one attestation in Yamatohama tz’ɨba ‘sword guard,’ which can be considered a borrowing.

103. tuwe 2.4 ‘cane’: We find Tarama dii ^A ‘handle’ and Ikema dii ^C ‘id.’ that seem related to MJ tuwe 2.4 ‘cane.’ However, such apparently cognate nouns are attested only in Miyako, and their segmental correspondence with MJ is irregular. Moreover, the unexplained semantic change ‘cane’ > ‘handle’ (or ‘handle’ > ‘cane’) makes the hypothetical cognacy doubtful.

107. sake 2.5 ‘salmon’: We only observe Yamatohama sakʰɜ ‘salmon,’ which is considered a Japanese loan.

The other nouns listed in Table 8 have not been attested in our sources.