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PKOCKKOINGS OK THK M A LACOLOGICA L SOCIKTY. 



EXPLANATION OF PLATEI I. 



Fig. 1. Cultellus cultellus. View from the right side, showing internal 



structure, etc. Nat. size. 

 ,, 2. Azor antiqtoahis. View from the right side, showing internal 



structure, etc. Nat. size. 

 ,, 3. Azor coarctatus. View from the right side, showing internal 



structure, etc. Nat. size. 

 A. anus; ^4. .4. anterior adductor muscle; C.C. caecum of the crystalline 

 style; D.G. digestive gland ; -Ex. S. proximal portion of the exhalent siphonal 

 chamber; Ex.S.' exhalent siphonal tube; F. foot; In. intestine; In.S. 

 proximal portion of the inhalent sij)honal chamber; In.S.' inhalent siphonal 

 tube; M. mouth; M.C. musculus cruciformis ; M.L. mantle-lobe; P. A. 

 posterior adductor muscle; P.P. protractor pedis anterior muscle; P.R.A. 

 retractor pedis anterior muscle ; P.B.P. retractor pedis posterior muscle ; 

 B. rectum ; S.R. ridge dividing the inhalent from the exhalent chamber 

 of the proximal portion of the siphon, and to which is attached the basal 

 part of the gill ; S.R.M. siphonal retractor muscle; St. stomach. 



