68, 



Pig. 9, Anterior portion of tiie sliell, and tne reriected 



margins of tl-ie foot just before tliey are brouglit 

 together and witadraism into the shell. 



Fig. 10. An animal as it appears -while feeding. 



Pig. 11. Posterior portion of a specimen about 1/2 mm long. 



Fig, 12. Transverse section of a specimen about 1 mm. long^ 

 showing the thickening of the ridges leading to 

 the base of the siphon, and the pushing in of the 

 ventral wall of the exhalent siphon. Taken near 

 the base of the siphon. 



Fig. 13. Posterior portion of a specimen about 2rani. long. 



Fig. 14. Transverse section of a specimen about 1 cm. long, 

 taken through the bases of the siphons. One of 

 the ridges is shovm joining the inhalent siphon. 

 The section also includes a portion of the -wall 

 attaching the exhalent siphon witli the dorsal por- 

 tion of the mantle. 



Fig. 15. End of the exhalent siphon of a specimen ,7 ram. 

 in length. 



Fig. 16, Projection of the mantle margin opposite the ex- 

 tremity of the anterior shell stripe, seen some- 

 •what obi i quel v. 



