592 MR. F. E. BEDDARD ON THE [ Dec. 3, 
agreement with Bucorvus in the fleshy 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. 
The patagial 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. 
Patagial muscles of Bucorvus abyssinicus. 
H, Humerus; Bi, Biceps; tp, b.r, tendon of tensor patagii brevis ; a', tendi- 
nous slip to pectoralis primus; 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, &e. vol. i. p. 529. 
