| OCR Text |
Show 296 MR. R. H. BURNE ON THE [Apr. 18, One muscle in the neck-region I have not been able to satisfactorily identify (Text-fig. 55. 29 a.) Origin: from the ventral surface of the last cervical and first dorso-lumbar vertebrae. Insertion : upon the ventral and lateral surfaces of vertebpe iv., v., vi., v i i . This muscle, the front end of which lies lateral to the longus. colli, can be separated with difficulty into at least three more or less separate bellies. The dorsal surface of the dorso-lumbar region of the vertebral column is covered by a layer of intermingled muscular and tendinous tissues that represents the back-muscles in a degenerate condition. Dermoehelys coriacea, anterior part of tlie vestigial muscles of tlie back. In this mass three parts can be distinguished by their position, although they are in no other way separable from one another:- a. Fibres running from spine to spine. These parts are contiguous in the mid-line, except where they are interrupted by the neural spines. b. Fibres that run beside the neural arches above the necks of the ribs. c. Fibres running from rib to rib. In front of the second pair of ribs these parts can be to a certain extent separated mechanically. In the anterior thoracic region parts b and c are strongly Vestigial Back-Muscles. (Text-fig. 56.) Text-fig. 56. |
