CIECULATOKY SYSTEM 



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1. The arterial system. 



From the ventricle arises a single large vessel, 

 the aorta. This gives off almost at once a large 

 visceral artery, which runs along the upper surface 

 of the liver to the top of the spire, supplying both 

 lobes of the Uver, the intestine, and the reproductive 

 organs. 



The aorta itself runs forwards along the right 

 side of the crop, between it and the common duct. 



Pio. 31. — Helix pomatia. Section taken along the axis of the shell, and 

 transversely to the foot. The sheU is represented by the thick 

 black line. (a. m. m.) 



A, tunbilicus. AG, albumen gland. S, nucleus of shell, C, crop. 

 J}, common duct. E, flagellum. F. foot. G» pulmonary sinus. HG, herm- 

 aphrodite gland. I, intestine. K, tidney. LIi, left lobe of Uver. MC, 

 pulmonary or mantle^^Tity. DAG, mucous glands. P. pedal gland. PC, 

 pericardifd cayity, PS, pedal sinus. PV, pulmonary vessels. R, rectum. 

 KL, right lobe of liver. BM, retractor muscles. S, spermatheca. SG, sali- 

 vary gland, U, ureter. V, ventricle. 



