62 



GUIDE TO THE CORAL GALLERY. 



Cases, the last having attached to its stalk a long tentacle armed with 

 Upright part, thread-cells. 



In Physalia, the " Portuguese Man-of-War " (Fig. 25), the air- 



FiG. 25. 



cr 



Physalia floating on the surface ; cr, crest ; p, a polyp ; pn, air sac. (After 

 Huxley; from Parker and Haswell's Zoology.) 



sac takes the form of a large pear-shaped bladder provided with a 

 many-chambered crest ; a mass of generative buds and feeding polyps 

 with long tentacles is suspended from the under surface of the 



