*(r/l)um

This root is attested in the NE Indian Areal Group, Nungish, and perhaps Qiangic, as well as in Himalayish (Hayu, Tshona). The proto-initial seems to have been *r-, though some reflexes have l-. It is possible that there is a connection with *s-lum or *z-lum ‘round’ (STC #143).

卵 OC *lwɑ̂n, GSR #179a ‘egg; testicle’; Li 1971: *luanx; Baxter 1992 #557: *g-ronʔ; Mand. luǎn.

In Baxter’s system, MC l- is always derived from OC *C-r-, that is, an initial r with a prefixed consonant (to be distinguished from *Cr- in which r functions as a medial). In other systems, MC l- may descend from simple initial *r-. Baxter 1992 gives two separate reconstructions for this word: *g-ronʔ (#557) and *C-ronʔ (#949, with *C unspecified). There is some reason to suppose that if the prefix *C- is to be reconstructed it would be a velar (Baxter 1992:387).

The correspondence between PTB *r- and Middle Chinese l- is well-attested. Although both the Chinese and PTB forms have a rounded vowel and a nasal final, the correspondences are problematic. No generally accepted OC/PTB cognates show an *-n/*-m correspondence. OC *ua (Li 1971) / *o (Baxter 1992) generally corresponds to PTB *o, not *u; for example, 脫 OC *hluat ‘remove’ (Li 1971); PTB *hlot; Mand. tuō. We would expect PTB rhyme *-um to correspond to OC *-əm (Li 1971); see examples in Gong 1995.

Gong 1995 #41 compares Chinese 卵, which he reconstructs *ruanx, with Written Tibetan sro-ma ‘nit’ (see #1172 PTB *s-row EGG / NIT, below), following Benedict 1976:190 (“Sino-Tibetan: another look”). Schuessler 2007:369 makes the same comparison, citing PTB *(s-)rwa rather than *s-row. For this comparison to hold, a nominalizing *-n suffix must be posited for the Chinese form (Schuessler 2007:74-75).
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