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CCELEKTERATA. 



The well-known "Portuguese man-of-war " (Physalia pelagica) 

 is the only species of the order that has received an English 

 name. It represents a suborder (order) for Claus, as do also the 

 Velellidae (Discoidese). 



Apolemia. 



Stephanomia. 



Agalma. 



Halistemma. 



Physophora. 

 Stephanospira. 



Athorybiidfs. 

 Athorybia. 



EhizophysidcB. 

 Ehizophysa. 



Physalia. 



Velellida. 

 Velella. 

 Porpita. 



Class III. ACTINOZOA. 



POLYPI. CORALLARIA. AtfTHOZOA. 



The digestive cavity not in contact with the outer wall of the 

 body, but separated by an intervening perivisceral space. 



The perivisceral space is radially divided into a number of 

 compartments by membranous partitions [mesenteries], in which 

 the reproductive organs are placed. Reproduction also takes 

 place by budding, by fission of small fragments separating from 

 the edge at the base [Gosse], as well as by ordinary generation. 

 The egg, in the latter case, develops into an infusorial-like germ, 

 with vibratile cilia and free locomotion [planula]. The sexes are 

 either united or distinct. 



The mouth is furnished with tentacles, hollow, and either 

 simple or fringed, capable of being withdrawn into the body- 

 cavity. No manducatory apparatus exists. 



The great majority are composite organisms, mostly provided 

 with a horny or calcareous secretion, known as the " corallum " 

 or "polypary." The corallum-tissue [sclerenchyma] presents 

 every gradation between the solid condition and the spicular 

 stage. For these animals collectively Huxley extends the term 

 " Coralligena." 



There are two subclasses : 



Tentacles simple ZOANTHARIA. 



Tentacles pinnately fringed ALCYONAKIA. 



