474 DR. J. MURIE ON SAIGA TARTARICA. [June 9, 
The remnant of, or aborted fibula, asin other Ruminants, is repre- 
sented by a short stalactic process of bone depending from the 
external tibial tuberosity, and by a small subquadrate-shaped bone 
impacted along with the tarsal elements at the tibial distal extremity ; 
the latter, as above said, takes the place of an outer malleolus. 
The tarsus is composed of five separate bones, and a sixth if the 
fibular distal appendage or separate tarsal-like end be included. 
These altogether are not so stout as in the Sheep or Chamois. 
The calcaneum is strong, of moderate length and thickness, and 
somewhat more than usually narrowed in cross thickness. It mainly 
articulates with the astragalus; but there is a facet which rests upon 
the upper surface of the cuboid portion of the combined naviculo- 
cuboid bone, and another for the infrafibular ossicle. 
The astragalus has the ordinary Ruminant type, but relatively is 
of small size, though its ligamentous pits and impressions are deepish. 
Its distal articulation is chiefly with the navicular portion of the 
scapho-cuboid. 
This combined scapho- or navicular cuboid bone is deep compared 
with its size. Its upper surface, or face of articulation with the 
astragalus, is biconcave and considerably scooped out. 
The single metatarsal shows little or no sign of segmentation. 
Like the metacarpal, it is of considerable length, but much the more 
laterally compressed, or its antero-posterior diameter is the greater. 
This fore-and-aft depth decreases from above downwards, and at the 
base or distal end becomes altered, so that it is broader across than 
from front to back. The upper two-thirds of the posterior surface 
is fluted; and at the top of the groove there rests a small sesamoid 
bone. The trochlear or digital articular eminences are deep, but not 
wide. Two pairs of sesamoid bones, affording pulley-superficies for 
the flexor tendons, lie behind the distal enlargement. 
As regards length, lateral compression, shape and number, the 
digits and phalanges of the hind foot agree closely with those of the 
fore foot. 
(C) The limb-structure compared.—In reviewing the appendi- 
cular structures I may, first, refer to the Table which I have drawn 
up to exhibit the comparative lengths of the limb-segments in a 
series of Ruminants. (See p. 475.) 
Saiga is there placed alongside the Sheep. The numbers attached 
to the names refer to the individual skeletons in the College of Sur- 
geons’ Museum, from which these measurements were taken. A 
single species of each group may serve for comparison, though of 
course this implies approximate rather than exact inferences. 
With regard to greatest breadth of scapula to its length, allowing 
the long diameter to be represented by 100, these are as under- 
noted :— 
38°1 Giraffe. 59°8 Bull. 68°0 Sheep. 
56°4 Goat. 60-0 Saiga. 68°1 Musk-Deer. 
59°0 Gazelle. 67°1 Fallow Deer. 69°6 Llama. 
These proportions, added to the general appearance heretofore men- 
