234 MR. G. E. DOBSON ON CAPROMYS MELANURUS. [Apr. 1, 



species C. pilorides, remarkable for the extraordinarily subdivided 

 condition of its hepatic lobes, first described by Say in 1822 1 . 



The genus, which includes four species — C. pilorides, C. brachyurus, 

 C. prehensilis, and 0. melanurus — is also remarkable for its very 

 limited geographical distribution, being confined, so far as we know, 

 to the islands of Cuba and Jamaica, where its species appear to be 

 the only indigenous representatives of the Order in these islands, as 

 it is more than probable that the smaller Rodents 2 which now infest 

 them were introduced. 0. brachyurus appears to be limited to 

 Jamaica, the other three species to Cuba. 



As the original description of C. melanurus consists of a few lines 

 only (see Monatsb. Akad. Berl. 1864, p. 384), 1 add the following 

 notes on its specific characters, taken from the two well-preserved 

 female specimens referred to above. 



Capromys melanurus (Poey), Peters. (Plate XVIII.) 



Smaller than the common Rabbit, with a long, thick, cylindrical 

 scaly tail clothed with long, rather coarse hairs, and with short, 

 nearly naked ears, shorter than the muzzle and rounded off at the 

 tips. The eyes are comparatively small ; the muzzle rather narrow, 

 terminated by the obliquely placed nostrils, which open sublaterally, 

 while between them and running down to the upper lip is a shallow 

 narrow groove becoming wider lower down. The hinder extremities 

 are longer than the fore, but do not much exceed them in length, 

 although the pes is very much larger than the manus ; the latter is, 

 nevertheless, large for the size of the animal ; the palm is deeply 

 concave, margined by five low rounded prominences covered by 

 tuberculated skin ; the pollex is quite rudimentary, protected by a 

 small blunt claw ; the other digits have prominent, convex, acutely 

 pointed claws ; the middle digit is longest, the fourth nearly equal to 

 it, the second comes next in length, and the fifth is still shorter. The 

 pes is more than double the size of the manus and nearly double its 

 length ; the hallux, though short, is not rudimentary and is provided 

 with a claw like that of the other digits, which have the same relative 

 lengths as the corresponding digits of the manus ; all are provided 

 with long, very strong, acutely pointed claws, much longer than 

 those of the manus. The animal is plantigrade, applying the whole 

 surface of both manus and pes to the ground. The plantar surface 

 is coucave behind the toes as in the manus, but there is no promi- 

 nent posterior plantar callosity. 



There are two mammary teats on each side, placed high up on 

 the sides of the body, on a level with a line drawn from the lower 

 margin of the scapula to the anterior crest of the ilium, as in Myopo- 

 tamus. In the male animal (which the writer has not seen) the 

 external generative organs probably resemble those of C. pilorides 

 (described by Prof. Owen in P. Z. S. 1832, p. 76); in the female 

 the orifices of the vagina and anus are placed on a conical prominence 



1 Journ. Acad. Nat. Sci. Pbilad. ii. p. 333 (1822). 



2 Hesperomys palustris, common in the Southern States of America, and the 

 ordinary European Eats and Mice introduced by ships into the islands. 



