llVlJl;nZ()A. 



47 



stems giving off whorls of slender hniuohleta bearing the uiiuutecui^ ^^ 3b. 

 and still more minute funnel-shaped ueniatophores. 



.1. ramom (Case 3b) has la-anched stems. 



lu Ar/laop/ieniapJunia, the '• Podded Corallin<-." ihe r. ' .. 



capsules are protected by a i>od-shaped receptacle formed i i.. ,i 



brauchlets which curve round and meet. 



Af/Jaophenia itrens* from .Java, is named on account of its severe 

 stiuo-iuy properties. Some species of this genus living in the tropi.s 

 attain a height of several feet, and it is dangerous to come in contact 

 with them. 



Fig. 8. 



\ 



'J> 



\.'' 



Hydractinia echinata on a shell of a whelk inhabited l>y a Hermit Crab. 



(Natural size.) 



II. HYDROCORALLIN^ OR CORAL-LIKE IIYDROZOA. 



The Hydrozoa of this group rescmlile the Reef Corals in forming Cases 2, 4. 

 a calcareous skeleton ; indeed, the Hydrocorallinie were sup|K.»«tl 

 to belong to the same class (Authozoa) jis the Corals, till Aga^-i 

 showed that Millepora was a true Hydrozoon. Iiat<r, ^losi-Uy. in his 

 classical work on the Challenger HydrocoralliuiV, confirmed Agassiz' 

 results, and proved that the Sti/lostiridip- were also Hydrozoa. In 

 all the llydrocorallines two forms of polpys (Fig. It!) occur, viz.. 

 gastrozooids, with nioutli and stomach, and teniaclc-likc dactylo- 

 zooids without a mouth ; the gastrozooids are contained in pit> 



