168 



SYSTEMATIC ZOOLOGY. 



ORDER III. SIPHONOPHORA. 



These may be defined as colonies of medusae, arising by 

 budding. In these colonies the medusae become special- 



FIG. 15. Diagram of a Siphono- 

 uhore. c, covering scale; d, 

 digestive sac ; f, float ; m, mouth 

 of feeding individual ; r, repro- 

 ductive bell; s, swimming-bell; 

 /, tentacle. 



ra '." 5>Trf/Al<jijW 



FIG. 16. Portuguese man-of-war 

 (Physalia'). After mgassiz. 



ized in different directions. This specialization in some 

 forms may go so far (figs. 15, 16) that we have the jelly- 



