276 MESSRS. B. C. A. WIXDLE AXD F. G. PARSONS ON [Nov. 3, 



which by cutting the rectus and turning its origin up, evidence 

 of the two heads could not be found. Lesbres (V.) says that in 

 the Pig, Sheep, and Goat the reflected head is absent ; we have, 

 however, paid special attention to the point in the Pig (11, 14) 

 and Sheep (46, 47), and are convinced that both heads are really 

 there. With regard to the crureus in Ungulates, we have often 

 noticed that it is more distinct than in many other orders of 

 mammals, and it rises from all three surfaces of the femur. Some- 

 times, as in the Ox (40) and Sheep (41), it is divided more or 

 less completely into an inner and an outer portion. The vastus 

 externus is usually larger than the internus, but in the Tapir 

 (61, 62) both Murie and ourselves were struck by the enormous 

 size of the vastus internus. The nerve-supply of the quadriceps 

 is alwaj^s the anterior crural. 



Anterior Tibial Region. 



Tibialis atiticus. — This muscle usually has a femoral origin 

 from the front of the external condyle, rising with the extensor 

 longus digitorum, as well as a tibial origin from a small part of 

 the upper and front portion of the tibia. 



In the Hippopotamus (3) the two parts are quite separate, the 



tibial portion being inserted into the base of the second (index) 



metatarsal, while the condylar part forms an arch in front of the 



ankle which binds down the extensor tendons, the two horns of 



the arch being attached to the bases of the index and minimus 



metatarsals. In the Suidas (4, 5, 11, 14) the two parts are also 



distinct, but the fibrous arch is not present, and they are both 



inserted into the index metatarsal and middle cuneiform bones. 



In all the other Artiodactyla, viz. Ohevrotain (22, also the " Napu 



Deer" described by Haughton XY., which is the Javan Ohevrotain), 



Yirginian Deer, Kylghau, Elk (30), Brocket Deer (29), Sheep 



(47, 48), Ox (35, 40), Goat (50, 52), and Antelope (54, 55), the 



arrangement is practically identical with that of the Duiker-bok 



(54), the variations being verj^ slight. In this animal (54) the 



femoral head is the larger, and opposite the ankle is pierced by 



the tibial tendon, it is then inserted into the inner side of the 



dorsum of the base of the large metatarsal bone, which is common 



to the medius and annularis digits. The tibial tendon, which 



pierces the one just described, runs to the ventral part of the 



inner side of the base of the same metatarsal bone. In the 



Perissorlactyla the same femoral and tibial origins are found in 



the Tapiridse (61, 62) and Equidae (63, 64, 65), and the same 



perforation occurs in the Horse, though we did not notice it in 



the Tapir (61). As to the Rhinoceros we have not sufiicient data 



to form an opinion. In the Subungulata the femoral origin is 



absent ; this is the case in both the Hyrax (74, 75) and the 



Elephant (80, 81, 84, 85). In the Hyrax its insertion is into the 



second metatarsal, while in the Elephant it is usually inserted 



into the first as well. It is always supplied by the anterior 



tibial neive. 



