120 PHYSIOLOGICAL SERIES. 



muscle that in the ascending series is last met with in 

 the Monotremes (see No. C. 139). Coraco-antebrachialis 

 (biceps) : both heads rise from the coracoid and unite near 

 their insertion ; the outer one is digastric, with a central 

 tendon where the muscle crosses the shoulder-joint ; the 

 muscle is inserted, as in many lower mammals, into both ulna 

 and radius. The coraco-brachialis : divided into two parts, 

 both of great size. The humero-antebrachialis inferior 

 unites with the coraco-antebrachialis before its insertion. 

 The aneoneus rises by four heads, respectively scapular, 

 coracoidal, and humeral (two) in their origin ; the coracoid 

 head is to a large extent represented by tendon. The 

 carpo-digitalis ventralis brevis (flexor sublimis digitorum) 

 is entirely confined to the hand and takes origin from the 

 annular ligament. The teres major is absent. 0. C. 64 Y /. 



C. 131. Right fore-limb of a Lizard (Varanus salcator}, showing 

 the deeper muscles. An accessory pronator (ulno-carpalis) 

 is present, crossing the arm from the inner and anterior 

 surface of the internal condyle to the radius above the 

 insertion of the epitrochleo-radialis (pronator teres) ; it 

 probably forms part of the ulno-radialis (pronator quad- 

 ratus). 0. C. 64 YM. 



Fiirbringer, Morph. Jahrb., Bd. i. 1876, p. 688 ; Mivart, 

 Proc. Zool. Soc. 1867, p. 775. 



C. 132. The nerves and superficial muscles of the right fore-limb 

 of a Crocodile (Crocodilus acutus). While the musculature 

 in general is weaker than that of the Lizard, there is a 

 marked preponderance in strength of the muscles of the 

 shoulder and upper arm over those of the fore-arm. 

 The muscles most developed are those concerned in the 

 dorso-ventral movements of the shoulder (dorsalis scapulae 

 [deltoid] and pectoralis) and in the extension of the elbow 

 (anconeus), movements of considerable importance to the 

 Crocodile in balancing and steering through the water. 

 The following comparisons may be made with Varanus : 

 The dorsalis scapulae (deltoid) is double. The coraco- 

 antebrachialis (biceps) has only one head. The coraco- 

 brachialis longus is absent. Between the humero-ante- 



