Fig. 13. 



1. A colony of a Gymnoblnstic zoophyte. Coryne vaginata. Natural 



size. 



2. A colony of a Gymnoblastic zoophyte. Syncoryne exima. Natural 



size. 



3. A polyp of the latter, much enlarged, to show a. mouth ; b. 



tentacles ; c, d. medusids developing. 



4. The Medusid freed from No. 3 and advanced in growth. About 



3 times natural size e. its mouth ; /. tentacles. 



5. Obelia geniculata. Natural size. 



6. A ' ' stock " of obelia geniculata, much enlarged g. nutrient polyps ; 



h. reproductive capsules with young medusids inside ; i. a freed 

 medusid seen from the side ; k. a freed medusid seen from beneath ; 

 /. mouth (in each medusid); m. reproductive glands; n. the 

 ccenosarc (in the stock) ; o. the horny tube. 



7. Stinging cells, " Nematocysts." Lower figure with the thread 



coiled within. Upper figure with the thread shot out p. ordinary 

 cell contents; q. nucleus; r. the "Trigger"; s, barbs; t, 

 thread. 



