48 



ZONITID^E. 



process, at the head of which the retractor muscle is given off. 

 The spermatheca is short and pear-shaped. The radula teeth are 

 arranged : 36 . 2 . 15 . 1 . 15 . 2 . 86, or 52 . 1 . 62. 



The central tooth is strongly tricuspid ; the adjacent teeth are 

 hardly tricuspid, only showing an exceedingly fine notch on some 

 of the teeth on the inner upper margin; the laterals do not 

 decrease much in size outwards and are evenly bicuspid.] 



Subgenus INDRELLA. 

 Indrella, Godwin-Austen, Proc. Mai. Soc. iv, 1901, p. 187, pi. 18. 



[Fig. 27. Indrella ampulla. 



Animal with shell removed from right side; head from above: X0'8. The 

 genitalia, X 1'8 ; the jaw and the teoth of the radula, X 144. spr. & sper., 

 spermatophore, position of ; m, muscle attachments ; m.r.e.t, muscle 

 attachment of right eye tentacle, beneath integument. 

 For explanation of letters in italics and numbers see figs. 2, 3, 4, and 1 6.] 



