GENERAL ANATOMY OF A CRAB. 



197 



In the anterior portion of the inner chamber notice a much 

 smaller flabellum which is carried by the second max- 

 illiped. 



8. Disarticulate and remove the three maxillipeds with 

 their flabella, in succession, and notice again the form 

 and position of the flabellum of each of them. 



9. Notice that while each gill is free from those on each 

 side of it, and from the outer and inner walls of the 

 branchial chamber, it is enclosed by a tough chitinous 



FIG. 101. 



FIG. 101. Upper surface of the "cardiac" pouch of the stomach of 

 Callinectes hastatus ; with the muscles removed to show the gastric mill. 

 (Drawn from nature by W. K. Brooks. ) 



(For explanation of letters, see Fig. 102.) 



cuticle, which is continuous, at the base of the gill, with 

 the calcified shell. "\Vhen the shell is moulted the chitin- 

 ous covering of the gills is also pulled off, as part of the 

 cast shell. 



10. Place a living specimen in water, and notice the 

 current which is drawn through the slit at the base of 



