PERONEAL MUSCLES IN BIRDS. 



1061 



The P. brevis is much stronger, with a good muscular origin from 

 the distal three-quarters of the shaft ; its tendon passes under 

 a iibrous bridge and flattens out to the usual insertion. 



TJpupidse. 



Upu]3infe. TJpupa epops{^ examples). — The P. longus is absent. 

 The P. brevis is large, from the distal three-quarters of the shaft, 

 including both fibula and tibia. The tendon flattens out to the 

 normal insertion. 



Bucerotin?e. Bucorvus (? species). Rhytidoceros undulattis. 

 Lophoceros erythrorhynchus. — In the Horn bills the P. longus is 

 absent, although I find in my notes that there is a degenerate 

 set of tendinous fibres which might possibly represent a vestige 

 of it. The P. brevis is very strong, arising from the lower 

 half of the shaft, fi-om the fibula and its fibrous continuation, 

 and from the adjacent surface of the tibia. The strong tendon 

 flattens out to form the usual insertion. In Bucorvus the 

 P. brevis was equall}^ strong but rather shorter. 



Striges. Athene 9^oci^^«. (3 examples). Bubo lacteus (2 ex- 

 amples), B. maculosus, B. maximiijS (2 examples). Asio otus. 



Text-fiir. 186. 



Gas^ 



Flex 



Pei'" 



6 ANT 



Peroneal muscles of Strix flanimea. 

 Right leg, outer view. Muscle strijied ; tendon dotted. 



P. BRE. Peroneus brevis. P. B. 1. Tendon of P. brevis. 

 Gastr. External head of Gastrocnemius. 

 Flex. Flexor muscle of foot. 

 Tib. Ant. Tibialis anticus. 

 >S1. Sling of tibialis anticus. 



