PERONEAL MUSCLES IN BIRDS. 



1049 



Accipiti^es. SerpentaiiiilfB. — I liave had no recent opportunity 

 of examining a Secretary bird, but I infer from Dr. Gadow's 

 statement (" Aves" in Thier-Reich) that both peroneals are present, 

 and that as P. longus is very large the condition is generalized and 

 thus like what exists among the Ciconiiformes. 



Vulturidse and Falconidse. Gypaetus barhatus. Tinnuncidi(,s 

 alaudarius . Falco peregrinus (2 examples). Aquila verreauxi. 

 Hcdiaetus leitcogaster. Ictinia mississipiensis. Circus goiddi. — In 

 all these birds both peroneals are present, but the P. brevis is the 

 more powerful and the P. longus tends to be reduced only to its 

 deep origin. In the Lammergeier there is the greatest re- 

 semblance with the normal arrangement. The P. longus has all' 



Text-fiff. 182. 



PLOW. 



P.dRE. 



f\NCHr 



Peroneal muscles of Falco peregrinus. 



Description and lettering as in Text-figure 179. 



Fib. Anterior edge of fibula. 



three origins, but the superficial origin is rather narrow and 

 partly reduced. In all the others the superficial and fascial 

 origins have practically disappeared, so that the muscle, as shown 

 in the case of the Falcon (text-fig. 182), almost exactly balances 

 the P. brevis, arising from the other side of the fibula and the 

 adjacent area of the tibia along the greater part of the length of 



