VENUS MERCENARIA LINN/EUS 



215 



pleural ganglia are connected with the pedal ganglia by cerebro- 

 pedal connectives, and with the visceroparietal ganglia by cere- 

 brovisceral connectives. The cerebral ganglia furnish the anterior 

 pallial nerves. The visceroparietal ganglia which, like the other 



FIG. 43. Nervous system of Anadonia anatiiia after Vogt and Yung, 

 Anatomic Comparee. c, foot; k, pedal ganglion; /, cerebro-pedal connective; 

 g, cerebral ganglion; h, cerebral connective; a, anterior adductor muscle; r, q, 

 anterior pallial nerves; d, liver; s, visceral nerve; /, cerebro-visceral con- 

 nective; e, gill;/, edge of mantle; n, branchial nerves; m, visceral ganglion; 

 o, posterior pallial nerves; b, posterior adductor muscle; p, lateral pallial 

 nerves. 



ganglia in Venus, are of a pink or yellow color, lie so close to 

 each other that they have the appearance of a single ganglion. 

 Behind the cerebrovisceral connectives this ganglionic mass 

 gives off two branchial nerves and two posterior pallial nerves. 



