COMPARISONS. 



With columns for Starfish and Sea-urchin, answer the 

 following questions: 



(1) What is the general shape of the body? 



(2) Are the radial canals inside or outside the hard body- 

 wall? 



(3) Do you find branchiae? 



(4) Are all the spines movable? 



(5) Is an Aristotle's lantern present? 



(6) How many divisions to the reproductive organs? 



(7) Are hepatic caeca present? 



(8) Do you find a branchial tree? 



(9) Do you find gastric pouches? 



Read the section on Asteroidea (pp. 276 to 278) and that 



on Echinoidea (pp. 280 to 282). 



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