ACALEPH^E. 



Peron (Fig. 92), is another very remarkable form of 

 constituted organisms. 



221 

 strangely- 



Having presented to the reader certain characteristic types of 

 Medusadse, we proceed to offer some general remark upon the organiza- 

 tion and functions of these strange creatures. We have, in short, 



Fig 90. Rhizostoma Aldrovandi. 



selected these types because they have been special objects of ana- 

 tomical and physiological study to some of our best naturalists. 



The Medusae have no other means of breathing but through the 

 skin. We remark all over the body of these zoophytes certain 

 cutaneous elongations, disposed so as to favour the exercise of the 

 breathing function. Certain marginal fringes of extended surface, as 

 well as the tentacle, are the special seats of the apparatus. The 



