Achaiinella and other Pulmonata. 345 



more developed side cusps, which overlap the median cusps, 

 than in those from Dominica. 



The marginal teeth of the former exhibit a o;reater ten- 

 dency to splitting into shar^i denticles on the cutting cusps 

 than those of the latter island. 



The Dominica lingual, in the only row counted, has 87-1- 

 87 teeth, one in the St. Kitts form has 57-1-57. 



These diiferences in the lingual membranes are noticeable, 

 but we believe, especially as the shells are identical, that 

 they are not of specific value. 



AsuplsLi99iilini» (^uceinea) nibesceiani, Dcsh. 



AVe are indebted to Governor Rawson for specimens (pre- 

 served in alcohol) of this species from Martinique. 



On examination of the jaw and lingual membrane, we 

 found that the species is not a 8uccinea, but an Amj)hibu- 

 lima,* in which genus it is placed by Beck (Index, p. 98) 

 and by H. and A. Adams (Gen. Rec. Moll., 129), although 

 Pfeiffer treats it as a Succinea and v. Martens (Die Ilellcccn, 

 ed. 2nd, 310) catalogues it in Succinea s. str.f 



The jaw agrees perfectly with that of the genus Am/pJiibu- 

 lima described by us (Ann. Lye. N. H. N. Y., X, p. 

 225, pi. xi, tig. 8). There are alwut sixty delicate ribs. 

 The lingual membrane has also the same general arrangement 

 as in that genus (I.e., fig. 9) with specific differences from 

 that of A. jjaiula, especially in the widely expanded, blunt, 

 median cusp of the central tooth, and in the /Succinea-Yike 

 cutting away of the lower margin of the teeth. The mar- 

 ginal teeth of A. ruhescens resemble those we have figured of 



Goeotis (I.e., pi. xi, fig. 7). 

 A. rubescens occurs also in the environs of Cayenne 



(Drouet, Moll, de la Guyane Frangaise, p. 49). 



*See our note on p. 345 of Journal de Conchyliologie, XIII, Oct., 1873. 



t Since sending; the above to the printer, we have received the Journal de Conchy- 

 liologie, 3d series, XIII, No. 4, Oct., 1873. Oq p. 324, is a description of the jaw and 

 anatomy of this species by Dr. Fischer, who suggests the subgeneric name Rhodonyx, 

 overlooking its generic identity with Amphibulima. 



