MUSCULATURE. 261 



fibers of opposite sides, passing diagonally posteriorly and dorsally from the 

 venter, meet along the median line. Here there is a narrow area devoid of spines 

 that runs the length of the vertebral column. On the fore Umbs the fibers extend 

 to the carpus externally, but not quite so far on the radial side. They insert 

 for a space of about 20 mm. on the distal ulnar margin and pass also into the 

 fascia covering the hand. Posteriorly the fibers encircle the lower leg, below 

 the knee and similarly become confluent witli the fascia investing the extremity 

 of the leg. 



The following secondary attachments were found: — (1) a small muscular 

 bundle, rather triangular in section, and di\asible into two main strands, arises 

 by a flat tendon from the posterior tuberosity of the head of the humerus, 

 sUghtly internal to the insertion of the pectoralis, and passes dorsad and caudad 

 some 65 mm. to the dorsolateral portion of the panniculus, with the fibers of 

 which it becomes united. This is the dertno-brachialis posterior of Fewkes. 



(2) A smaller and more nearly cylindrical muscle takes origin by a separate 

 tendon just external to the last, from the posterior tuberosity of the humerus; 

 it is of about the same length, but cur\es distinctly cephalad. Its fibers run 

 forward into those of the panniculus at about the position of the large spines 

 on the fore shoulder. Fewkes names this muscle the dermo-hrachialis anterior. 



(3) A thin sheet of muscle which appears to be the dermo-cervicis triangularis 

 spreads over the back of the neck and inserts with the panniculus into the distal 

 part of the ulna. The two muscles of opposite sides are continuous dorsally 

 through a thin aponeurosis. 



(4) What Fewkes has called a dcrmo-dorsi ceruicalis in the Echidna exists 

 also in Zaglossus (Plate 1, fig. 1, m). It arises just back of the shoulder by mus- 

 cular strands from the eighth and ninth ribs, and is connected by aponeurosis 

 with the posterior ends of the trapezius and the latissimus dorsi. These strands 

 unite to fonn a flat muscle about 70 mm. long and 17 mm. wide at the point of 

 insertion into the dorsal part of the panniculus. It passes anteriorly before 

 uniting with the latter, and then expands to a width of some 34 mm. The 

 muscles of opposite sides apparently do not unite to form an ellipse on the back 

 such as Fewkes describes for the Echidna, but at their anterior approximation 

 the two muscles are separated by about 10 mm. They are more or less intimately 

 connected, however, with a thin sheet of non-muscular tissue that covers the 

 dorsum. This sheet is attached along either side at about 30 mm. from the 

 midline, from the eleventh rib and medially from the eleventh dorsal spine 

 posteriorly. Toward the sides of the body it becomes thickened with fat and 



