CALYCONECTAE. 



145 



br- 



nectocalyces if two are present (Fig. 118), there is a deep groove or 

 pit in the jelly called the hydroecium, into which the contractile 

 stem with its cormidia can be retracted. In the jelly of the upper- 

 most nectocalyx is a 

 space lined by large 

 vacuolated cells, and 

 sometimes containing 

 an oil-drop. This is a 

 dilatation of the upper 

 end of the central 

 canal of the stem and 

 is called the somato- 

 cyst. 



Each cormidium 

 consists of two medu- 

 soid individuals the 

 one of these is a 

 sterile and the other 

 a fertile medusoid. 

 The sterile medusoid 

 consists of a bract or 

 liydropliyllium, a' 

 siphon (trumpet- 

 shaped polyp), and a 

 tentacle, while the 

 fertile one is a gono- 

 phore. The hydro- 

 phyllium is the bell 

 of the sterile medu- 

 soid; it possesses 

 rudiments of the 

 radial canals which 

 radiate from an api- 

 cal dilatation the 

 pJiyllocyst (Fig. 120) 

 which corresponds 

 to the somatocyst of 

 the nectocalyx and is 

 connected with the central canal of the stem. The siphon is the 

 manubrium of the sterile medusoid, which is displaced from its 

 umbrella and has a trumpet-shaped mouth at its free end. The 



L 



FIG. 120. Endoxia Esclischoltziia. female eudoxid of 

 giaca Kochii (after Chun), with helmet-shaped hydrophyl- 

 lium, br containing phyllocyst, siphon p, tentacle t, and 

 three gonophores of different ages, go 1 , go 3 , go 3 , with eggs 

 in the manubrium. 



