1901.] THE ilUSCLES OF THE L'NGULA.TA. 699 



distal phalauges of a variable uumber of digits. In the Hippo- 

 potamus (1, 3) tendons pass to all four digits. G-ratiolet (III. 

 pi. X.) draws and describes two distinct fleshy bellies which unite 

 below the dorsal annular ligament and again divide for the four 

 digits. In the Siiidie the number of digits supplied varies a good 

 deal : for instance in the Domestic Pig (-i, 5, G, 7) there are three 

 fleshy bellies which are distributed with varying detail to all four 

 digits ; in the Eed-River Hog (11) no tendon goes to the minimus ; 

 in one Peecai-y (13) there are four fleshy bellies which altogether 

 divide into eight tendons for the four toes in such a way that the 

 medius has one tendon for each phalanx, the annularis also three 

 tendons, while the index and minimus ha^'e one each ; in another 

 Peccary all the tendons are distributed to the medius and 

 annularis. 



In the Camelidce (15, 17, 18) there are slips for the medius and 

 annularis, the forn\er having two. 



In the Tragulida? {'20, 21, 23) all four toes are supplied, though 

 here again the medius has two tendons. 



In the Cervidas (25, 26, 27, 28) and (xirartidie (29) only the 

 medius and annularis are provided with tendons. In (25) and 

 (28) we found an extra small origin from the ulna. 



In the Bovid* (32, 33, 36, 38, 39, 43, 41, 48, 49) there are 

 two tendons for the medius and one for the annularis ; the muscle 

 is double almost from its origin, the more ulnar of the two 

 dividing for the medius and annularis, while the radial one passes 

 to the medius only and iu many cases at all events ends in the 

 middle phalanx of that digit. The Musk-Ox (37) differs from 

 the rest of the Bovidas in having a tendon to the index from the 

 radial of the two fleshy bellies. 



The Tapir (53, 54, 55) has tendons for the index, medius, and 

 annularis, and our specimen (54) had in addition a slender slip 

 for the minimus. Murie (XVII.) noticed a small origin from the 

 idua in his animal (55). 



In the Equidse (56, 58, 60) there is a small origin from the 

 radius as well as the usual one from the external condyle ; the 

 muscle divides into the usual t\AO fleshv bellies, one of M-hich 

 ])asses to the terminal phalanx of the m.edius, while the other joins 

 the so-called extensor minimi digiti. 



In the Ehinoceros (63) there are tendons for all three digits. 



In the Procaviidae (67, 68, 71) all four digits have tendons, and 

 the same observation applies to the Elephant (74, 77, 78). 



Two points strike one in reviewing this muscle in the Ungulata. 

 The first is that an extra origin from one of the forearm-bones is 

 often found ; the other that the muscle divides high up and forms 

 many tendons for few toes, so that two or more phalanges of one 

 toe may each be acted upon by its own tendon. This is the more 

 curious when one thinks of the one function which the fore-foot 

 of an ungulate is called upon to play ; but the possible expla- 

 nation is that the muscle acts chiefly from the foot, and that when 

 this is planted on the ground the different slips act one after 



