PLATE XII. 



Fi<;. 42. — Central tooth of the radula. 



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



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



Fig. 4n. — Third lateral tooth of the radula. 



Fig. 46.— Fourth lateral tooth of the radula. 



Fi<;. 47. — Fifth lateral tooth of the radula. 



Fig. 48. — Sixth lateral tooth of the radula. 



Fig. 49. — Cross section of a digital tentacle. ('. L. x 15. 



C, cirrus. 



SH, sheath. 

 Fh;. 50. — Longitudinal section of the tip of a digital tentacle. C. L. X 20. 



A, artery. 



G, G, annular grooves between ridges. 



LM, fasciculi of longitudinal muscles. 



N, nerve. 



K, suctorial ridge. 



SH, tip of sheath of, cirrus. 



T. transverse muscle layer. 



V, vein. 

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