•580 



DE. J. ANDEBSOJT ON AECTOMTS DICHROTJS. 



A. dichrous. 



A. attmm. 



Lengtli taken on the dried skins. 



lS-5 



7-5 



10 



2-2 

 0-5 

 0-4 

 2-9 

 0-5 

 0-5 



1 6-5 to 1875 

 5-0 to 6-5 

 1-5 to 175 



2-05 



0-8 



0-6 



2'9 



0-8 



0-52 







Fore foot (palma) to end of toe, without claws 





Hind foot (planta) to end of toe, without claws 







As far as one can make out from the above, it would seem that the two 

 species in question bear considerable resemblance to each other in size. This 

 is equally manifested in the dimensions of the skull as shown below. Mr. 

 Blanford [1. c. p, 124) has ranged together a series of cranial measurements 

 (in parts of a metre) of several species ; and taking his points to start from, 

 the relative sizes of the skulls of the animals from Yarkand and Kabul are 

 below seen at a glance. The greatest difference appears in ttie width at 

 the zygomatic arches ; but injury to those of A. dichrous renders the dia- 

 meter a doubtful one. The dimensions are in millmetres. 



1 



! 



1 

 A. dichroies. ' A. aureus. 



Length from ocripital plane to anterior end of nasai 



Breadth across widest part ot zygomatic arches 



90 



48? 



20 



33 



U 



15 



20 



45 



32 



94 

 57 

 17 

 SH 

 19 

 16 

 20 

 66 

 S5 











,, lower jaw from angle to alveolar margin .... 





Circumstances have caused my comparisons with the Marmot skulls in 

 the British Museum to be meagre ; and moot jjoints suggested by Mr. 

 Blanford I shall not here enter into. The skull marked A. bobac {A. gi- 

 gantea, Brandt, from Kamtschatka) agrees in most respects with that of 

 A. dichrous, but is considei-ably larger, the mandibular angle of the former, 

 however, being more produced and stronger than in the latter. Of two 

 other skulls, also labelled A. bobac (? = J. himalayanus, Hodg.), one ap- 

 pears young, the other fully adult. A. dichrous much resembles the 

 younger specimen, but it diiiers from the more aged one in its postpala- 

 tiues being narrower and deeper, in less emargination of the bone above 

 the hinder angle of the lower jaw, and in the mandibular body being less 

 arched, A skull marked^, thibetanus (Tibet, Hodgson) (? = i[. hetnacha- 

 lanus, Hodg.) is evidently young, inasmuch as the processes and occipito- 

 parietal crests are undeveloj)ed, with other signs of immaturity. Its post- 

 palatine region is comparatively shallow and wide, and the posterior free 

 border of the mandible is relatively straighter than that of A. dichrous. 



In my former notice I described the colour of the skin of A. dichrous, 

 wliich, as the trivial name implies, is of two shades — a rusty yellow above, 

 and a dark rich brown on all the underparts, tail included. The hair, 

 moreover, is long and remarkably harsh in texture, although there is an 

 under-fur, so to speak, wliich is shorter, weaker, and dark-coloured. 



It still appears that there is good ground for the specific distinction 

 of A. dichrous, although the A. aureus of Blanford agrees in several 

 respects. Whether the animal incidentally referred to by Dr. Griffith 

 as having been obtained at an altitude of 11,000 feet in Afghanistan, but 

 heretofore undescribed, is identical with my A. dichrous, as Mr. Blanford 

 seems inclined to believe, is a matter still sub judice. On my return t<i 

 Calcutta, I hope to be able to elucidate certain of the doubtful points 

 raised but requiring further investigation. 



