COMPARISONS. 



With one column for Crayfish, the other for Sow-bug, 

 give answers to these questions: 



(1) Are head and thorax united? 



(2) Are the eyes on movable stalks? 



(3) How many pairs of walking-feet, counting the 

 pincers as such? 



(4) Where are the gills? 



(5) Are both exopods and endopods present? 



Read the accounts of Decapoda (pp. 226 to 229) and 

 Tetradecapoda (pp. 229 to 231). 



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