106 
JANK I. IIOBERTSON. 
Text-fig. 23. 
DAo. 
B. 
Diagram of the development of the aortic arches. Ventral view. 
A. About Stage 26. b. About Stage 33-34. c. About 
Stage 35. A. A. The six aortic arches of which 1 and 2 are 
incomplete. B. C. Bulbus cordis. Car. Dorsal carotid 
artery, Car. e. External branch of carotid. Car. i. In- 
ternal branch of carotid. D. Ao. Dorsal aorta. D.A.B. Dorsal 
aortic root. h. Heart. Hy. 1. Branch to hyoidean hemibranch. 
Hy. 2. Hyoidean efferent artery. L.A. Lingual artery. P. A. 
Pulmonary artery, s. c. Short-circuiting channels between the 
afferent and efferent branchial vessels. V. A. Ventral aorta. 
