296 



HYDRA 



-cnb 



Fig. 75. — Hydra. 

 A, a nijiiiaiucyst contained in its cnidoblast {cnh), showing its coiled filament 



and the cnidocil {c>ic\ 

 11, the same after extrusion of th*; thread, showing; the larger and smaller harbs at 



the base of the thread ; ?u(. the rmcleus of tht: cnidoblast. 

 C, a cnidoblast, with its contained nematocyst, connected u itli one of the process(J•^ 



nf a nerve-cell {n7\ c). (From Parker's Bic>/i\i,y : after Schneider.) 



ill as a hollow pouch : the free end of the latter is continued 

 into :i hollow coilttl ftkinienl, and from its inner surface 



