Jaw and Lingual Dentition of Puhnonata. 185 



Coecilianella G-undlachi, Pfr. 

 St. Martin. Dr. H. E. Rygersma to Mr. T. Bland. 



Mr. Bland has already noticed this species, in Ann. Lye. Nat. Hist, of 

 N. Y., XI, 152, 1875, where a detailed description of the jaw and lingual 

 membrane will be found. 



I add a figure of the jaw (pi. xiii, fig. D), with a still more enlarged 

 view of a portion of it (fig. G), to show the character of the ribs. As 

 stated in the article referred to, these ribs are quite different from those 

 described by Sordelli for C. acicula. 



PI. xiii, fig. H gives a camera lucida drawing of a central, lateral and 

 marginal tooth. Fig. 1 gives a still more magnified view of the transition 

 and marginal teeth, not drawn, however, by camera lucida. 



Jaw low, wide, slightly arcuate, ends attenuated ; whole surface cov- 

 ered with about 22 crowded, broad, flat ribs, denticulating either margin. 



Lingual membrane long and narrow. Teeth 18-1-18, with 4 perfect 

 laterals. Centrals with their base of attachment long, narrow, their re- 

 flected portion about one half the length of the base of attachment, tri- 

 cuspid ; the middle cusp stout, with a short blunt cutting point, side cusps 

 subobsolete, but with small, distinct cutting points. Lateral teeth with 

 their base of attachment subquadrate, much longer, and very much 

 broader than that of the centrals, the reflected portion short, stout, tri- 

 cuspid, the middle cusp very stout and long, reaching the lower edge of 

 the base of attachment, beyond which projects the short, stout cutting 

 point; side cusps subobsolete, but bearing distinct, though small cutting 

 points. There are four perfect laterals, the fifth tooth being a transition 

 to the marginals, by the base of attachment being lower, wider, not ex- 

 ceeding the reflected portion, with one inner large cusp bearing one outer 

 large cutting point representing the outer cutting point of the first four 

 lateral teeth aud one inner, still larger, cutting point, representing the 

 middle cutting point of the first four laterals, and one smaller, outer cusp, 

 bearing one small, sharp, bifid cutting point, representing the outer side 

 cutting point of the first four laterals. The sixth tooth has the largest 

 cutting point bifid. ^ The balance of the teeth are true marginals. They 

 are very low, wide, with two low, wide cusps, bearing each several irreg- 

 ular, blunt cutting points. 



The dentition of this species is, as would be anticipated, of the same 

 type as the allied Coecilianella acicula as figured by Lehmanu (Lebenden 

 Schnecken Stettins, p. 128, pi. xiii, fig. 43, and Sordelli, 1. c, fig. 26). 

 The jaw, however, has no appearance of the "brace" like ribs described 

 in that species by Sordelli (Atti Soc. Ital. Sc. Nat., XIII, 1870, 49, pi. i, 

 fig. 25). The ribs are quite like those figured of Helix Lansingi (Ann. 

 Lye. Nat. Hist. N. Y., XI, p. 75, fig 2 A) although they are narrower. 



