1870.] DR. J. MURIE ON SAIGA TARTARICA. 457 
others behind are subquadrate, increasing consecutively in length 
and width, the last being double the width of the first. The xipho- 
sternum («) flat, and obliquely downwardly bent, has a broad proxi- 
mal base, which narrows suddenly and, becoming spatular, termi- 
nates with a slightly expanded tip. 

Three-quarters underview of sternum, with cartilages and portion of the ribs 
attached. p.s¢. Prxsternum. m. st. Mesosternum. sz. Xiphosternum. 
2. Of the Cranial Framework. 
(A) Different Aspects of the Skull.—In several particulars the 
skull of Saiga tartarica is isolated or unique amongst living Rumi- 
nants, though, as will be shown hereafter, one or more ancient 
types foreshadowed the peculiarities. Pallas (/. c. tab. iii. figs. 9 & 
10) has given reduced figures of it in profile, and in front fore- 
shortened; and Dr. Gray, in his ‘Catalogue of Mammalia in the 
British Museum,’ 1852 (tab. vi. figs. 1 & 2), has likewise repre- 
sented similar views. In those figures, however, the horns and 
general outline of the skull seemingly have been more attended to 
than definition of the coadapted osseous areas; hence fresh repre- 
sentations are, in a great measure, a necessary adjunct to a descrip- 
tion of the bony elements of this éizarre Ruminant’s skull. The 
skull of the hornless female and the horned male necessarily exhibit 
different aspects *. 
Dealing with the latter, when looked at sideways (shown in 
fig. 5), the prominent features may be summarized as follows :— 
* Skeletons of the Swiga hitherto have been rare in this country. Besides 
the Hunterian and the present specimen, I only know of one other, which was 
obtained some years since by the Museum of the University of Cambridge— 
where in addition are two skulls (male and female), all being from wild animals. 
Professor Newton obliged me by kindly transmitting the two latter crania for 
my inspection. Comparing these with that here described and the College of 
Surgeons’ specimen, I detected little differences worthy of special record other 
than sexual, 7. e. diminution of osseous sutural ridges and absence of horns in 
the female. I may also add that the tympanic bulla in the female were rela- 
tively more inflated than in the male; in the latter laterally compressed and 
very ovine. 
