222 BULLETIN OF THE 



m. muscle. 



me. membraneous wall overarching c near its anterior end. 



m. s. arteria? musculo-spinales. 



vis. arteriae musculo-spinales of the head. 



n. nasal artery. 



n. p. neural process. 



o. ophthalmic artery. 



p. palatine artery (= maxillary of Parker). 



p. c. e. art. post, cerebri ext. D. S. 



I.-IX. First to ninth pairs of aortic roots (arches). 



1-6. First to sixth pairs efferent branchial vessels. 



1/-6'. First to sixth pairs afferent branchial vessels. 



T"-5". First to fifth visceral arches. 



Fig. 1. A sketch of a dissection of the efferent branchial vessels and the result- 

 ing aorta of Chlamydoselachus anguineus, natural size. On the right of the figure 

 the vessels are sketched in the outline of the roof of the mouth, to the point of 

 emergence from the tissue surrounding the proximal ends of the gill arches indi- 

 cated on the left oval outlines. The left internal carotid artery is not shaded, 

 and is sketched for a short distance only to show its course in the chiasm, at 

 which point the cephalic aorta is broken for the sake of clearness. The end of the 

 cranial aorta, and its branches connecting it with the pituitary plexus, are drawn 

 somewhat enlarged. 



Fig. 2. A semidiagrammatic figure of a portion of the vascular system of the 

 same fish, showing the relations of the arterial and venous vessels, as seen from 

 the left side. Approximately natural size. At * the coronary artery is cut off, 

 nor are many of its branches shown. The venous vessels, heart, and ventral aorta 

 are left unshaded. The common and internal carotids have been displaced up- 

 wards, aud the anastomotic branch broken for sake of clearness. 



