CAMCENA. 105 



Subgenus PSEUDOBBA MollendorfF, 1891. 



Pseudobba v. MOELL., Nachrbl. D. M. Ges. 1891, p. 202, type H. 

 mamilla. Obba (typical part) MARTENS, not Gray. 



The shell in this group is heavy, solid, rudely sculptured, with a 

 rather large umbilicus. The subgenus is evidently more nearly 

 allied to Phcenicobius than to the continental Cam&enas. Type C. 

 mamilla, pi. 19, fig. 9. 



The living animal, as figured by Quoy and Gaimard (Voy. de 

 1'Astrol. pi. 7), agrees with that of Camcena in external features. 



Jaw of C. quoyi horse-shoe shaped, the ends attenuated; cutting edge 

 with a distinct median projection (pi. 15, fig. 11). Viewed in profile, 

 the anterior surface is concave (pi. 15, fig. 12). The color is dark 

 chestnut. Anterior surface smooth ; showing by transmitted light 

 fine wavy lines parallel with the margins. (Schako, from a half- 

 grown specimen; Mai. Bl. xx, p. 169). 



Central and lateral teeth with the mesocones only developed, as 

 in Camcena. Marginal teeth with a large, oblique, bifid rnesocone 

 and an ectocone ; also closely resembling the teeth of Camcena (pi. 

 15, fig. 13, central, lateral and marginal teeth, and fig. 14 a lateral 

 of C. quoyi, seen in profile). 



The species of this subgenus inhabit northern Celebes and the 

 Sangir Is. It is a satellite group of the Philippine Island Camsenas, 

 which has spread southward like a few Obbas and Cochlostylas. 

 The dentition is the same as in Camcena, but the jaw (o/aw imma- 

 ture specimen of quoyi) lacks ribs ; so it seems that in this genus, as 

 in the West Indian Caracolus, the presence or absence of ribs is not a 

 generic character. From Quoy's remark that the jaw of mamilla 

 Is not different from that of French Helices, we presume that it is 

 ribbed in that species. 



Species. 



C. mamilla Fer., vi, 212. C. linmeana Pfr., vi, 214. 



C. quoyi Desh., vi, 213. C. tirmaniana Anc., viii, 269. 



undulata Q. & G., not Fer. 



Subgenus CAM^ENELLA Pilsbry, 1893. 



Camcenella PILS., Proc. Acad. Nat. Sci. Phila. 1892, p. 398, type 

 Helix platyodon Pfr. (Feb. 14, 1893). 



Shell depressed, subglobose, solid, imperforate, banded and macu- 

 lated, with about 5J whorls, the last descending in front. Surface 



