THE PRAWNS. 



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sition, are in fact the same. But, in the prawn, the abdomen 

 is much larger in proportion to the cephalothorax ; the 



Fia. 71. Palamon jnmnwrn!^is (about ^ nat. size). A, female ; 

 B, filth thoracic appendage of male. 



basal scale, or expodite of the antenna, is much larger ; 



the external maxilHpedes are longer, and differ less from the 



succeeding thoracic appendages. The fii"st pair* of these, 



which answers to the forceps of the crayfish, is chelate, 



but it is very slender ; the second pair, also chelate, is 



always larger than the first, and is sometimes exceedingly 

 13 



