| OCR Text |
Show 1880.] MR. O.THOMAS ON MAMMALS FROM ECUADOR, 399 they slightly diverge behind in B. alleni. (5) The last upper molar, instead of being subquadrate, as long as it is broad, and nearly as large as the first, is subtriangular as in Procyon, much broader than long, and considerably smaller than the first molar, as shown in the table of measurements. (6) The top of the coronoid process of the lower jaw (see fig. 3) is different in shape from that of B. gabbi; and in the latter the angular process is further from the condyle than in B. alleni. When the external characters of B. gabbi are described, I feel quite sure that further points of difference will be found between these two forms from such very distant localities as Costa Rica and Ecuador. The skull of Bassaricyon is so absolutely different from that of Cercoleptes that Mr. Allen did not think of comparing the two ; and I fully agree with him in thinking this animal more nearly allied to Procyon and Nasua than to any of the other Procyonidae, though in size it is more similar to Bassaris. Fig. 3. Lower jaw of Bassaricyon alleni. The external resemblance of this species to Cercoleptes certainly seems to be an instance of mimicry, which, so common among insects, is somewhat rare among Mammalia. It is, however, very difficult to understand how being mistaken for Cercoleptes could in any way benefit Bassaricyon; but when more of the habits of the latter are known we may hope to be able to guess at the true use of the likeness. Mr. Buckley unfortunately did not take any especial notice of the habits of this animal, as both he and the Indians thought it to be merely the common Kinkajou. It is much to be hoped that more specimens of this interesting genus will be found ; and I would draw the attention of collectors and others to'the only external means of distinguishing it-namely, the flatness of the head and the greyness of the face as compared with the high head and yellowish face of the Kinkajou. |
