64 



in which case my former name of O. sculptorum might be retained 

 for that to which it was applied. 



"2, 3, and 4. ITie museums of Western Europe do not, that I 

 can learn, contain any portion of the Siberian Argali, Ovis ammon of 

 Pallas, that might serve for comparison with the Rocky Mountain 

 Sheep of North America, 0. montana of Desmarest; but as the Kam- 

 tschatka Argali is described as a distinct species, O. nivicola, by M. 

 Eschscholtz in his Zoologischer Atlas, (differing from the two pre- 

 ceding in its inferior size, and in wanting, it would appear, the pale 

 disc surrounding the tail, so conspicuous in both the others,) the 

 probability is thus enhanced, that the Siberian and Rocky Mountain 

 species are not the same, however closely they may resemble. The 

 descriptions of 0. Ammon would seem to apply in everj' particular to 

 the O. montana, though it is still probable that actual comparison of 

 specimens would lead to the detection of some discrepancies, as ge- 

 nerally, but not always, happens in like cases. I may notice, that 

 while Mr. Drummond affirms that the horns of old rams of 0. mon- 

 tana ' attain a size so enormous, and curve so much forwards and 

 downwards, that they effectually prevent the animal from feeding 

 on level ground*,' the same had previously been remarked by Strah- 

 lenberg of the Argalis of Siberiat, and no doubt is equally obser- 

 vable in the Rass of Pamir. The finest specimen of a head of the 

 Rocky Mountain animal, of seven heads of adult males examined, 

 is in the collection of this Society, and gives the following admea- 

 surements : horns 3 feet .5 inches over the front ridge, and 17^ inches 

 round at base, where the front angles are 4| inches apart. They 

 number nine years of growth, which successively give 9, 7|, 6§, 5, 

 A~, 4, 2^, 1^, and 1, inches. They are nearly equilaterally tri- 

 angular, but bulge a little between the angles, having the inner or 

 front angle obtusely prominent, the posterior double, or forming a 

 second plane at a slight angle with the superior one, and the infe- 

 rior angle (if such it can be called) much rounded off: the greatest 

 depth of the horn is about 6 inches ; from base of front angle to tip 

 they measure 1 1 inches ; and the tips apart 26 inches. They are 

 everywhere strongly furrowed across, more particularly in front, the 

 intervals between the grooves swelling out considerably ; and they 

 gradually become, as in all the rest of the genus, more compressed 

 to the extremity. 



" Of the O. nivicola of M. Eschscholtz, that naturalist writes : 

 ' The specimen described is a male in winter garb, measuring 5 feet 

 (French ?) in total length, and 2 feet 5 inches high. Its outer coat 

 is of a yellowish grey colour, brighter on the under parts, and in- 

 clining to straw-yellow on the head and neck ; the markings in front 

 of the limbs are of a rust-colour : horns equilaterally triangular, 3 

 inches thick at base, and gyring outwards to form one complete 

 spiral circle, 10 inches in diameter, and having their points directed 



* Fauna Americana-horeaVis. 



t Description of the northern parts of Europe and Asia. — Eng. Trausl., 

 p. 332. 



