AMPHIBULIMA. 



241 



The island Martinique is, therefore, the only place where A. rubes- 

 cens seems to be undoubtedly found, and in moderate abundance. 



Subgenus PELLICULA Fischer, 1856. 



Pellicula FISCHER, Actes Soc. Linn. Bordeaux, xx, p. 449 ; type 

 Ll - Succinea depressa " (= appendiculata). 



Sliell incapable of containing the soft parts, oval, shaped like a 

 depressed, open Succinea ; the spire extremely short or depressed, 

 composed of less than two whorls, smooth; aperture extremely large, 

 (he short, oblique, posterior columella more or less built out in a thin 

 blade-like appendage. ' Type Succinea appendiculata Pfr. 



The two species composing this subgenus are very similar in shell 

 characters, A. depressa having the spire shorter than in A. appendic- 

 ulata, and the posterior part of the outer lip more dilated; the cuticle 

 being olivaceous or reddish-brown. In A. appendiculata the spire 

 projects somewhat more, the color is white or very pale buff, and the 

 appendage on the columella is more strongly developed. Some shells, 

 however, are difficult to assign. In both species the shell is very 

 thin, somewhat pellucid, sculptured with slight growth-wrinkles and 

 some faint, subobsolete spiral impressions. The soft parts offer more 

 satisfactory characters, depressa being larger and blackish, with only 

 about 23 plaits on the jaw, while appendiculata is smaller, white, with 

 a jaw composed of about 40 plaits. 



Dr. Paul Fischer has ably discussed the relationships of the two 

 species, and I have reproduced the descriptions of shells given by 

 him, and those of the animal given by Maze ; merely adding that 

 specimens with the apical characters of depressa sometimes have a 

 well-developed columellar appendage. 



Succinea haliotidea Mittre and S. aperta Lea are referred to this 

 group by Pfeiffer (Nomencl. Hel. Viv. 1878, p. 231), though with a 

 mark of doubt. The first is apparently an Omalonyx, the second a 

 Hawaiian Succinea. 



A. APPENDICULATA (Pfeiffer). PI. 63, figs. 49, 50, 51, 52. 



Shell oval, rounded in front, tapering and subrostrate behind, of a 

 whitish color. Spire pa pillar, projecting. Right margin of the lip 

 not reflexed, inserted on the columella in front of the apex; columel- 

 lar appendage strongly developed. Length 12^-, width 8 mill. 

 (Fischer.) 



