FELIS SPELAVA. 139 
§ 2. Phalanges. a. First Phalanges.—The first phalange, or phalangiole, of the first 
digit, or thumb, is very short and of greater width than depth. The proximal articulation 
(Pl. XXI, fig. 6, a) is set obliquely to the dorsal face of the bone, so that the internal 
descends lower than the external edge. By this arrangement the first can be opposed to the 
other digits as in the Quadrumana, though the first metacarpal has no movement whatever 
of revolution. The palmar edge of the articulation is notched (fig. 6, ) to receive the 
elevation on the same surface of the metacarpal, so that it gives but little hindrance to the 
action of the flexor muscles. On each side of this are two small eminences for the 
adductor and abductor medii, the flexor brevis pollicis not being differentiated in the genus 
Felis. ‘The extensor longus is attached by an intermediate cartilage to a similar eminence 
on the dorsal surface, the tendon also passing on to the claw phalange. The distal arti- 
culation is terminal, and sits evenly on the bone; it is convex vertically, and slightly so 
transversely, so that a slight movement of rotation is allowed to the claw phalange ; it is 
much wider on the palmar than on the dorsal surface: immediately above the palmar 
edge is a deep depression for the reception of the flexor tuberosity of the claw phalange 
when the flexor muscles are in action. ‘The small lateral expansion of this articulation 
prevents the retraction of the claw so completely in this digit as in the others, but as it is 
raised from the ground it is in no danger of being blunted by accidental contact ; its 
position also on the inner side would prevent its being in the way of the animal. We 
have met with four specimens of this bone from Sandford Hill and Bleadon Caves ; they 
vary in size from that of the ordinary Lion to that of the same proportions as the other 
large bones we have described. 
The first phalanges of the remaining digits (figs. 7, 8, 9, 10) are very similar in their 
general character; the shafts being nearly cylindrical and slightly arched, and much 
smaller than the wide proximal articulations (a); the latter are deeply notched on the 
palmar edge (4) to receive the palmar ridge of the metacarpal. ‘The palmar surface also 
is furnished with small eminences for the insertion of abductor and adductor muscles 
and bear on either side two well-marked tuberosities to which are attached the ends of a 
strong ligament, the infra-phalangiole annular, through which, as through a pulley, pass 
the tendons of the flexor profundus and the flexor sublimis on their way to the claw 
phalange : the distal articulation is shaped like a pulley, and extends higher up on the 
palmar than on the dorsal surface, and bears a depression on the dorsal edge for the 
tuberosity of the second phalange. 
The first phalange of the third and fourth digits (figs. 8 and 9) resemble each other 
so closely that it would be impossible to determine to which of these two digits an isolated 
bone belonged ; that of the second digit is very much the stouter, and slightly the 
shorter, and is curved outwards, while that of the fifth is very much more slender, and is 
bent considerably inwards. All are easily distinguished from those of the hind paw by 
their greater slenderness and by their cylindrical section. ‘The large size of the proximal 
articulation and the tapering form of the bone in the Bear, and the small size of those in the 
