ANATOMY OF A MACTRA. 



ma na b 



Ficr, 88. ANATOMY OF A MACTRA. 



Explanation of Fig. 88, — Anatomy of a inactra ; one valve of the shelJ, 

 the corresponding half of the mantle and tlie branchiae have been removed 

 on the left side : — c. the shell ; — 7n. the mantle ; — ?na. the anterior muscle ; 

 — mp. the posterior muscle ; — b. the mouth ; — t. the tentacle ; — e. the sto- 

 mach; — as. appendix of the stomach; — i. the intestines; — -/. the liver; — p. 

 the foot ; — co. the heart traversed by the rectum (r) ; — ts. the superior tube 

 into which the anus (a) opens ; — ti. the inferior or respiratory tube ; — br. the 

 branchiae of the right side ; — ga. the anterior ganglia ; — na. nerves arising 

 from them; — ng. inter-ganglionic nerves; — gp. posterior ganglia; — np. 

 nerves arising from them and distributed to the mantle. 



