NATURAL SCIENCES OP PHILADELPHIA. 45 



ences are not such as suggest specific distinction, especially as the 

 shell furnishes no grounds for doubting the specific identity of the 

 forms. Nor by the shell alone does there seem to be two species. 

 Mr. Bland has given a detailed account of the species in Journal 

 de Conchyliologie, XXI. 342, October, 1873. 



Amphibulima rubescens, Desh. 



Mr. Bland and myself are indebted to Governor Rawson for 

 specimens preserved in spirits of Succinea rubescens, Fer. of 

 Martinique. 



On examination of the jaw and lingual membrane, I found 

 the species to be no Succinea, but an Amphibulima, in which 

 genus it is placed by H. and A. Adams (Gen. Rec. Moll.), and by 

 Beck (Index), though Pfeiffer treats it as a Succinea, and von 

 Martens catalogues it in Succinea, s. str. (See note 1 to p. 345 

 of Journ. de Conch., Oct. 1873, 3d series, XIII.) 



The external appearance of the animal has nothing peculiar. 

 The head appears blunt and short, the tail long and pointed, 

 without any mucus pore. There is no distinctly marked loco- 

 motive disk to the foot, over the whole breadth of which the 

 transverse muscles pass. The reticulations of the surface of the 

 animal seem large and coarse in proportion to its size. As far 

 as can be judged from alcoholic specimens, the tentacles and e^'e- 

 peduncles seem short and stout. The respiratory and anal orifices 

 are under the mantle on the right side. The external orifice of 

 generation is behind the right eyepeduncle. 



On opening the animal from above, the generative S3'stem is 

 found as usual, lying on the right of the animal. It occupies the 

 whole of the visceral cavity in front of the shell, lying upon the 

 stomach. The testicle (see plate VIII., fig. 4) is a globular mass 

 composed of long caeca. It lies imbedded in the liver. The epidi- 

 dymis is not greatl}^ convoluted. It passes between the stomach 

 and intestine, at the cul-de-sac of the former, on its way to the 

 ovary. The latter organ is, as usual, tongue-shaped. The ovi- 

 duct is long and greatly convoluted. The vagina is short, 

 receiving at its lower portion the long duct of the small, globular 

 genital bladder. The penis enters the vagina close to the common 

 opening. The sac of the penis is not long, is stout, cylindrical, 

 blunt at apex, where it receives the vas deferens, just above the 

 insertion of the retractor muscle. There are no accessory organs. 

 The genital system is very much the same in its general arrange- 



