142 



•vvith the exception of the one now under uotice, we fiud that that 

 finger has only three bony phalanges*. There are, however, several 

 characters present whicli appear to belong esclusively to the present 

 genus, such as the form of the snout and nostrils, the singular mark- 

 ings on some of the membranes, and the peculiar quahty of the fur. 



EXPLANATION OF PLATE LIV. 



Fig. 1. Mystacina tuberculata, three-fourths of the natūrai size. 

 a. Head of the šame, of the natūrai size. 

 į & c. Cranium of the šame, of the natūrai size. 

 d. Magnified representation of the front teeth of the šame. 

 Fig. 2. Magnified representation of the front teeth of Nyctinomus dilatatus, show- 

 ing the resemhlance between them and the šame parts iu Mystacina 

 tuberculata. 



3. On the Jamaican Cyclotus, and the Description of 



TwENTY-ONE PROPOSED NeW SpECIES AND ElGHT NeW 



Varieties of that Subgentjs from Jamaica, By the 

 HoN. Edward Chitty. 



Before entermg upon the task of description, it seems advisable to 

 offer a few observations upon the difficulty which has hitherto sur- 

 rounded this group of CrjclostomidcB inhabiting Jamaica. 



The late Professor C. B. Adams, in Contr. to Conch., No. 8, p. 

 140, et seq. wrote an article upon it; and although the required 

 study enabled him to add seven new species to the former Jamaican 

 list, a perusal of his paper will show that he laboured under great 

 doubts and without clear satisfaction as to the result. The fact is, 

 that almost all the species in the Jam. Cat. of Adamsf, 1851, from 

 No. 68 (for C. Buffianus, No. 67, is not a Jamaican, but a South 

 American species— ;^t/e Adams and Mr, Bland, who found dupHcates 

 in South America), to No. 77 inclusive, run so much into one another 

 in outward form of the mere shells, wanting the opercula, that it is 

 next to impossible to classify them. There is also the diflSculty of 

 young and old shells intermingled, which, as regards some of the 

 species, renders the " confusion worse confounded," particularly in 

 the young of C. Jamaicensis, and the more mature of C. crassus. 



The group in ąuestion, and many others, lead me to the firm con- 

 viction that, unless the differences are very marked, a single specimen 



* A similar peculiarity occurs in the genus Centurio, vhich, when first de- 

 seribed by Dr. Gray, was thought to be a native of the Old World, but there viras 

 some doubt as to the exact locality from ^vhich it had been received. But other 

 ėxaniples have been since obtained from the New World, and its near alliance 

 with the tailless Phyllostomida satisfactorily established. The existence there- 

 fore of four phalanges in this finger in Centurio cannot be considered, as in 

 Mystacina, as an exception to a general rule, but on the contrary as a further 

 extension of it. 



f "VVheneverthe name " Adams" is mentioned in these Communications, the late 

 Professor C. B. Adams, of Amherst College, America, is referred to, unless other- 

 vrise specified. 



