402 MR. O. THOMAS ON MAMMALS FROM ECUADOR. [May 4, 



30. Cholcepus hoffmanni, Peters. 



A y oung skin and skeleton from Balzar, showing clearly the pre- 

 sence of only six cervical vertebrae, and six specimens from Sara- 

 yacu. There is also a skin from the latter place which appears to 

 be referable to C. didaciyhts, Linn. ; but, without seeing the skele- 

 ton, I hesitate to state for certain that the two species are found 

 together in the same locality. One of the Sarayacu skulls shows 

 scarcely a trace of the usual inflation of the pterygoids ; the absence 

 of this inflation in certain species of the Tbree-toed Sloths caused 

 Dr. Gray to separate the genus Arctopithecus from Bradypiis^ ; but 

 this instance of its absence among the Two-toed Sloths shows that 

 it is not a character which can be relied upon for generic distinc- 

 tion. 



31. Bradypus infuscatus, Wagl. 



A series of seven specimens from Sarayacu, and one from Balzar. 

 The specimens show well the extraordinary amount of variation that 

 occurs among the Sloths, there being no two skulls or skins exactly 

 alike. The Balzar specimen has the soft straight hair on the face 

 extending on the head to a distance of 2| inches from the tip of the 

 nose ; no other specimen that I have seen has this hair extending 

 more than to just above the eyes, a distance of about one inch. 

 There is, however, nothing special about the skull of this specimen. 



32. Priodontes maximus. 



Basypus maximus, Kerr, Linn. Syst. Nat. p. 112, 1792''. 

 Basypus giganteus, Et. Greoif. & Cuv., Cat. Mamm. Mus. d'Hist. 

 Nat. p. 207. 1802. 



Basypus gigaSy Cuv. Regne Anim. i. p. 221, 1817. 

 Two specimens from Sarayacu. 



33. Tatusia kappleri, Krauss. 

 Two specimens, Sarayacu. 



This species, like Pteronura sandbachii, was hitherto only known 

 from the Surinam region. These two specimens, however, agree 

 exactly with those which the British Museum received some years 

 ago from Dr. Krauss himself, except that one of them has a fifth 

 claw on the fore as well as on the hind feet. The genus Tatusia 

 has normally the rudimentary bones of a fifth toe on the fore feet; 

 so that the occasional development of a fifth claw was quite to be 

 expected. 



34. Tatusia novemcincta, Linn. 

 Tatusia peb a, Desm. 



One specimen from Sarayacu. 



35. Xenurus lugubris, Gray. 

 One specimen from Sarayacu. 



1 P. Z. S. 1849, p. 69. 



* Cf. Ann. & Mag. N. H. eer. 5, iy. p. 396, 1879. 



