PERONEAL MUSCLES IN BIRDS. 1055 



Ilimantopus nigricoUis. Recurvirostra avocetta. Hmmatopus 

 ostralegus. Vanellus vanellus {3 examples). Charadrms pluvialis. 

 Rhynchcea capensis. 



In all these the P. longus is rather a small muscle with a broad 

 superficial, slight fascial, and very little deep origin from the edge 

 of the fibula. It narrows rapidly to a long tendon which gives 

 off a broad anchor and ends in the usual slip to III. The 

 P. brevis is always reduced, arising only from the proximal part 

 of the fibula and passing into a long slender tendon which 

 passes down the leg parallel with the tendon of the longus, dips 

 under a fibrous bridge at the distal end of the tibio-tarsus, and 

 then passing under the slip to III flattens out to the usual in- 

 sertion. In the Avocet, two examples of the Lapwing, and in the 

 Oystercatcher, the brevis was reduced to a slender ligament which 

 arose from the distal end of the tibio-tarsal shaft in about the 

 position where it would normally pass through a fibrous bridge, 

 and passed across the tarsal joint to be lost in the fascia? under 

 the slip to III. 



Chionidae. Chionis alba. — The P. longus is present with all 

 three origins, the deep being very feeble. The muscle passes into 

 a very long tendon which has the usual broad anchor and slip to 

 III. The P. brevis is also present but extremely feeble, a few 

 fibres from the fibula passing into a delicate tendon with the usual 

 insertion . 



Glareolida?. Glareola prat'mcola (2 examples). — Precisely as in 

 Chionis, the tendon of the feeble P. brevis being still longer and 

 moi'e slender. 



Thinocorythida?. Thinocorys lnT^Qcie^. — The P. longus is as in 

 the Glareolidse and Chionid^e, but the P. brevis is stronger, with 

 an extensive origin from the fibula passing into a long tendon 

 with usual insertion. 



OEdicnemida?. (Edicnemns scolopax. — The P. longus is large 

 and strong, with all three insertions passing into a rather shorter 

 tendon with broad anchor and strong slip to III. The P. brevis 

 is represented at most by a vestigial tendon. 



Parridse. Hydrophasianus cMrurgus. Phyllopezus afrkanus. 

 Jacana jacana. Asarcia variabilis. — In all these long-toed, long- 

 legged Ja^anas the P. longus is rather large with superficial, 

 fascial, and good deep origins. The broad band of muscle then 

 passes into a very long tendon which gives ofl" a wide but short 

 anchor and is continued as the slip to III. The P. brevis arises 

 from the upper third of the fibula and adjacent tibia and gives 

 rise to a very long tendon which flattens out to the usual 

 insertion. 



L a r i . 



Laridee. Larus argentatus, L. ridibundus. — The P. longus has 

 only the superficial origin, and the muscle converges to a very 

 long tendon which gives oflT a broad anchor and then forms the 

 usual slip to III. The P. brevis arises only from a small 



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