20 ANATOMY OF VERTEBRATES. 



On reflecting the skin from the under part of the head in 

 Myrmecophaga jubata, there is seen a feeble developement of a 

 panniculus carnosus in the form of thin transverse fasciculi 

 occurring at intervals of from two to three inches, where they 

 underlie the rami of the slender elongated under-jaw. These 

 muscular strips {dermogulares) have their attachments exclusively 

 in the integument, and aid in accommodating its movements to 

 the alternating expansion and contraction of the great gular dila- 

 tation near the base of the tongue. The transverse fasciculi 

 are crossed by a longitudinal strip of cutaneous muscle (dermo- 

 labialis posticus) on each side of the under part of the head and 

 neck ; the strip emerges from beneath the fore part of the great 

 subpectoral gland; it diminishes in breadth and increases in 

 thickness as it extends forward, assuming near the mouth the 

 character of a muscle independent of the skin, where, passing 

 beneath the tendon of the retractor anguli oris, it is inserted into, 

 or blends with, the fibres of an accessory portion of the orbi- 

 cularis oris. 



A shorter longitudinal muscular strip (dermolabialis anticus) 

 arises from the integument below the fore part of the preceding 

 muscle, becomes free as it advances, and is inserted into the 

 proper orbicularis oris. 



The flattened and slightly separated fasciculi of the dermo- 

 abdominalis arise from the fascia covering the anterior and in- 

 ferior part of the sternum and contiguous sternal ribs ; also from 

 a median raphe of the subcutaneous fascia, attached to the linea 

 alba, and extending two-thirds of the way towards the pubis. 

 The anterior two-thirds of the above muscular sheet are joined 

 by a broad layer of similar flattened fasciculi covering the side of 

 the thorax, and the muscle so formed passes obliquely downward 

 and outward, converging to form a thick fleshy band, about two 

 inches broad, which is continued along the inner and upper part 

 of the thigh, and becomes slightly twisted prior to its attachment 

 to the aponeurosis covering the knee-joint. 



The posterior portion of the dermo-abdominalis consists of 

 thinner and more scattered flattened fasciculi which pass outward 

 and downward, and, as they diverge from the median line, are 

 lost in the subcutaneous fascia covering the tendinous expansion 

 of the obliquus externus abdominis. Between the dermo-abdomi- 

 nalis and the proper abdominal muscles there is a moderately 

 thick layer of elastic cellular tissue. 



In the dissection of the head of the Great Anteater, three pairs 

 of long and slender muscles are met with, which relate to the 

 movements of the head. 



