Anatomy of Gorgomd^. 



99 



Watcr-vascalar canals: the passages which ramify through- 

 out the coenenchyma and are Hned with endothelial cells; the 

 canals are usually divisible into frhnary and secondary systems. 



Spicules: calcareous bodies of various forms deposited 

 throughout the coenenchyma, and often in the body walls and 

 tentacles of the polyps. 



The names given to the various forms of spicules are taken 

 from Kent's article,' "On the Calcareous Spicula of the Gor- 

 gonaceee." 



The other terms used are either familiar to students or will 

 be explained in the text. 



ZOOLOGICAL POSITION OF GORGONID^E. 



Sub-Kiiii^doni Ccelenterata : animals with radial sym- 

 metr}'-; a common gastro-vascular cavity, but no true stomach; 

 a mouth which is used both for ingfestion and etjestion. 



Class AcTiNozoA: coelenterates with an oesophageal tube 

 or gullet and gastro-vascular cavity divided by vertical mesen- 

 teries; no alternation of generation. 



Order Alcyonaria: actinozoans, in which the polyps pos- 

 sess eight fringed tentacles. 



Family Gorgonid^:" "Alcyonaria possessing a compound, 

 adherent polypary; provided with a sclerenchyma of a sub- 

 erose consistence, disposed after the manner of bark around a 

 sclerobasic axis, which axis assumes the form of a simple stem 

 or ramifying branch." 



Sub-Family Gorgonince: Gorgonidas whose common sclero- 

 basic axis is for the most part or entirely flexible, and is either 

 of the consistence of horn, or suberose. 



1 "On the Calcareous Spicula of the Gorgonaceze: their Modification of 

 Form, and the Importance of their Characters as a Basis for Generic and Spe- 

 cific Diagnosis." By Wm. Kent, F. Z. S. &c. Monthly Microscopical Jour- 

 nal, February i, 1870, p. 76. 



2 The definition of Gorgonidae is that of M. Edwards in his "Histoire 

 Naturelle des Corallaires." 



