COMPARISONS. 



With two columns, one for Oyster and Clam and one 

 for Squid, answer the following questions: 



(1) Is there a distinct head? 



(2) Are there cephalic tentacles? 



(3) Is there a bivalve shell? 



(4) Is the siphon, if present, a part of the mantle? 



(5) Did you find any eyes? 



(6) Are adductor muscles present? 



(7) Is there a bivalve shell? 



(8) Are the gills leaf-like or plume-like? 



(9) Are there jaws? 



(10) Is there a lingual ribbon? 



(11) Are there branchial and systemic hearts? 



(12) Is there an ink-sac? 



Read the accounts of the Acephala (pp. 202 to 208) and 

 of the Cephalopoda (pp. 208 to 212). 



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