PLATE XII. 



Fk;. 42. — Central tooth of the radula. 



Fiii. 43. — First lateral tooth of the radula. 



Fig. 44. — Second lateral tooth of the radula. 



Fio. 4.1. — Third lateral tooth of the radula. 



Kii;. 4(). — Fourth lateral tooth of the radula. 



Ki,;. 47.— Fifth lateral tooth of the radula. 



Fio. 4.S.— Sixth lateral tooth of the radula. 



Fi(i. 49. — Cross .section of a digital tentacle. ('. L. X 15. 



C, cirrus. 



SlI, sheath, 

 p,,;. 50,— Lontritudinul section of the ti]i (.f a (lii;il:il tentacle. C. h. X 20. 



A, artery. 



(t, G, annular grooves between ridges. 



LM, fasciculi of longitudinal muscles. 



N, nerve. 



R, suctorial ridge. 



8H, till of sheath of cirrus. 



T, transverse lunscle layer. 



V, vein. 



