THE ANTHOZOA 



The Anthozoan zooid is further characterised by the following 

 anatomical features : — The coelenteron is not a simple cavity, as 

 in the Hydroid zooid, but is divided by a number of radial folds 

 of tissue into a corresponding number of radial chambers. These 

 radial folds of tissue are called mesenteries, or by German authors, 



Flo. II. 



1.— Section through tlie stoniotlaenm of Adamsia rondektU. UiaKnimniatic. cc, ectoilemi 

 showing elongate ciliated epithelial cells, two kinds of gland cells, and nematocysts. Beneath 

 tiie ectodenn is a layer of nerve tibrils. mg, niesogloea, containing tibrils and a few stellate 

 cells; en, endodenn composed of cohnnnar ciliated cells and coiiUining two kinds of gland 



2.— Ecto<lenn cells from the body wall of Corynadis riridis, partly i.solated. 



8.— A portion of epithelium from the tentacle of Anemoniu sidcata, consisting of tlireo 

 supporting cells and one sense cell. 



4._A cnidoblast willi enclosed neniatocyst from the tentacle of Anrnwnia sulcata. 



5._Two ganglion cells from the ectodenn of the peristome of .-iMfmonin suh-nta. 



a.—Au epithelio-musiiilar cell from the extended tentacle of Adamsia ronilcletii. fia. The 

 same from a contracted tintacle. 66 and Cic Endoderm cells with symbiotic zooxanthellae from 

 the tentacle of -4ii<i(io»i" Mi/c'fK. 



7^ 7n._Two gland cells from the stomodaeum of Ancnwnia sulcata, ib. A flagellate cell 

 ft-om the same species. ,„..,„ x, ., 



8.— A gland cell from the stomodaeum of Anenumm sulcata. (2 orignial ; all the others 

 after O. and R. Hertwig.) 



sarcosepta or simply septa. There is no objection to the use of 

 the term sarcoscptura, but the term septum must be avoided, 

 because it denotes a distinct set of structures in one of the groups 

 of the Anthozoa. In this chapter the term mesentery will always 



