342 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 85 



cleus, the outside marked by a thin deposit of fine calcareous 

 granules. 



This species comes from the mountains of the central north coast 

 of the Isle of Pines. Here we have on the west the Sierra Casas 

 and facing it across the river some two miles distant, the Sierra 

 Cabal las, while to the north of this is the Sierra Colombo, and 

 about 3 miles northeastward is the Sierra Bibijagua, All these iso- 

 lated blocks harbor distinct races, which we here recognize. 



Of the animal of Chondropoina {Chondropoma) dissolutum, 

 Gundlach ^^ says: Animal whitish, especially the tentacles and snout, 

 neck flesh-color. Head with a purplish tinge. The tip of the ten- 

 tacles a little thicker and brownish. Head and neck grayish but 

 with many black dots which form a V-shaped area upon the head 

 behind the base of the tentacles, and a second similar one behind the 

 snout, which becomes darker posteriorly. 



Torre has examined IMorelet's types of Cyclostoma vespertinum in 

 the British Museum and of them he says : "Three specimens so labeled 

 in Morelet's handwriting. They are, however, the same as Chondro- 

 poma dissolutum Pfeiffer from the Isle of Pines. The locality Pal- 

 en(j[ue, Mexico, is evidently a mistake." 



Pfeiffer's Chondropoma dissolutum must, therefore, give way to 

 the older Chondropoma vespertinum Morelet. 



Distribution of the subspecies of C. (C.) vespertinum is shown in 

 figure 100. 



KEY TO THE SUBSPECIES OF CHONDROPOMA (CHONDROPOMA) VESPERTINUM 



Shell prevailingly brown. 



Length of decollated shell more than 19 mm vespertinum 



Length of decollated shell less than 17 mm , colombense 



Shell prevailingly flesh-color. 



Shell very thin bibijaguense 



Shell not very thin . caballosense 



CHONDROPOMA (CHONDROPOMA) VESPERTINUM VESPERTINUM Morelet 



Plate 30, Figure 14 



1851. Chondropoma vespertinnm. Morelet, Te.stacea novissima insula Cubanae et 



Americae Centralis, pt. 2, p. 19. 

 1854. Chondropoma dissolutum Pfeiffer, Malakozool. Blatter, vol. 2, pp. 158-159. 

 1858. Chondropoma dissolutum Pfeiffer, Novitates conchologicae, vol. 1, p. 95, 



pi. 26, figs. 12-16. 



We have discussed the use of the name 6'. (C.) vespertinum of More- 

 let, who does not help us in the restriction of it to a definite subspecies 

 except that we know from his Helicina constellata that he collected 

 in the Sierra Casas. Pfeiffer's figures of C. {C.) dissolutum also 



" Malakozool. Blatter, vol. 3, p. 130, 1856. 



