6 Journal of the Asiatic Society of Bengal. [N.S., XIX, 
to assume the dorsal position. This common subclavian artery 
divides into right and lefi subclavians (r. s., |. s.) which run 
on either side of the vertebral column. In Hemidactylus there 
are two independent subclavian arteries arising from the right 
systemic aorta. Near the base of the arm each subclavian 
divides into two, the vertebral and brachial arteries. 
(i) The Ver ce artery (ve ) runs forwards along the ver- 
tebral column and in its course gives off branches from each 
side alternately ehick enter the vertebral canal. 
(ii) The Brachial artery (br.) goes to the arm, first giving 
off a branch, the Subscapular (se. = to the scapula. The 
brachial has the usual course in the a 
(C) The Intercostal arteries (in. a. Three pairs of these 
arise from the right systemic arch ; they supply the body-wall. 
After giving off the subclavian artery, the right systemic 
_ erosses the middle line to enclose the left systemic similarly ; 
finally, it runs towards the alimentary canal along the mesen- 
teric artery, partly enclosing it, and ramifying in the same 
manner as the artery itself. The ligament is composed of 
very strong fibres of connective tissue, and may perhaps serve 
the purpose of keeping the aorta and intestine in position 
within the body-cavity during the active contortions of 
the body in rapid movement. 
II. The Left Systemic Arch (Fig. 1,1. a.) becomes dorsal 
like the right, and runs along the inner ventral border of the 
left lung; but before its union with the right arch to form 
the dorsal aorta it gives off the following branches :— 
(A) The Mesenteric artery (m.) arises from the left sys- 
temic arch about half an inch before the latter unites with the 
right arch; it is a fairly 8 vessel, and the left arch is 
noticeably diminished behind its origin. The mesenteric 
divides into two branches, which run side by side, enclosed by 
the longitudinal ligament described above, till they reach the 
gut; the two branches then separate, and distribute their 
blood to the different parts of the intestine. The ultimate 
distelbution of the branches is indicated in fig. 3, along with 
the ramifications of the ligament. 
(B) The Left Gastric artery (g’.) arises about midway 
between the origin of the mesenteric and the junction of the 
right and left arches. It is a small narrow vessel, running 
the left of the stomach, over which it is distributed. This 
vessel was however absent in two cases; in one case it arose 
very close to the union of the two systemic arches. Wieder- 
sheim (16) gives an instructive sketch to show the heart and 



