THE EXTREMITIES OF ORYCTEROPUS CAPENS1S. 590 



part, too, from the outer edge and a small part of t lie anterior face of this ligament, and 

 from the tendon of the biceps. At t lie inferior extremity of the tibia the mnsele 

 suddenly contracts, and passes tendinous under a very strong ligamentous pulley which 

 is shared by the extensor lt<<lh<cis. Two tendons are developed from this mnsele, one of 

 which passes to the inner side of the base of the metatar il of the hallux ; while the other, 

 after coursing down the side of the foot behind the former tendon, is inserted into the 

 anterior part of the inferior edge of the ento-cuneii'orni bone, and has also a slight com- 

 munication with the base of the metatarsal. 



This muscle, as I have described, possesses but one terminal tendon in Datgpns. 



In the Ai and Anteater, according to Meckel 1 , the tibialis milieus has two bends of 

 origin, which, however, meet in a common tendon which is inserted into the rudiment 

 of the hallux. Meckel hints that the external of these two factors may repr< ent the 

 extensor of the hallux. 



Dr. Ilg 2 describes in Cynocephalus spltinx a differentiated slip from this muscle, which 

 he terms " abductor hallucis longus," and states to be absent in man. It was fused at 

 origin with the tibialis anticus, and was inserted into the plantar aspect posteriorly oi 



the metatarsal of the hallux. 



This muscle, according to Burdach 3 , has two terminal tendons in Cercop i I h ecus ; but in 

 Innus and Cynocephalus one of these belongs to a differentiated muscular slip. He holds 

 that in each case the supernumerary muscle or tendon must be regarded as an abductor 



longus hallucis. 



The description of the tibialis anticus in Nycticebus tardiyradus is thus concluded b\ 

 Mr. Mivart and Dr. Murie : — "There is no trace whatever of any division of the tendon 

 of this muscle, a fortiori not of its muscular part " 4 . 



Church describes, in the Orang, a splitting into two parts of the tendon of this muscle, 

 as well as of that of its serial homologue in the hand, the extensor ossis met a carpi pollicis \ 



Prof. Huxley, in his lectures on the Mammalia at the Royal College of Surgeons, 

 remarked that the division of the tendon of the tibialis anticus was, in the Chimpanzee, 

 carried up into its muscular fibres, in some cases quite to their origin, so that the 



anterior portion had been described by Cuvier and others as a distinct muscle— th 



abductor hallucis longus. The tendon of the extensor ossis metacarpi j 

 this Ape, according to Prof. Huxley, double. In the same course of lectures, the 

 terminal tendons of both of these serially homologous muscles were described as double 

 in the Gorilla, in the Orang, and in Hylobates. This differentiation of the tendon did 



not, however, extend to the muscle itself 6 . 



Soemmering describes, in his work upon Human Anatomy 7 , a division of the tendon 

 of the tibialis anticus before insertion, the larger portion terminating at the cuneiform 

 bone, the smaller at the metatarsal of the hallux. 



According to Henle, the tendon of the tibialis anticus in Man divides before its inser- 



' Op. cit. p. 624. 8 Op. cit. p. 39. J Op. cit. V . 45. 



-ol. Soc. February I860. 

 Times and Gazette, 1864, April 



5 Nat Hist. Rev. Jan. 1862, pp. 83 and 88. 



Loc 



VOL. XXVI. 



4 



