592 



MR. F. E. BEDDARD ON THE 



[Dec. 3, 



agreement with Bucorvus in the fleshi/ insertion of the adductor 

 longus on to the lower border of the femur. The accessory semiten- 

 dinosus is distinctly double as in Aceros and is attached by a short 

 tendon to the adductor, though the direction of this tendon is some- 

 what different to what is found in Aceros. 



lihe j)ataginl muscles of Bucorvus (fig. 4 ) are particularly interesting ; 

 as in other Hornbills, the tendon of each just at its commencement 

 is reinforced by a tendinous slip derived from the pectoralis primus ; 

 in Bucorvus there is in addition a tendinous slip from the biceps. 



Fig. 4. 



Patagial muscles of Bucorvus ahyssinicus. 



H, Humerus ; Bi, Biceps ; if.p, b.r, tendon of tensor patagii brevis , a', tendi- 

 nous slip to pectoralis immus ; Bs, junction of this with a tendinous slip 

 to biceps ; a, tendinous slip which unites tendon of tensor patagii longus 

 with pectoralis. 



The fact that this slip is attached not to the tensor longus but to the 

 tensor brevis does not in my opinion invalidate its homology with 

 the so-called " biceps slip " of other birds. Bucorvus is moreover 

 not the only " Anomalogonatous " bird with a biceps slip ; these 

 structures I have found in Colius as a well-developed fleshy muscle 

 united to the tendon of the tensor longus ; but its description by 

 Prof. Fiirbringer ^ has anticipated the novelty of the present remarks. 



'^ Untersuchungen zur Morph. u. System, der Vogel, &c. vol. i. p. 529. 



