SEA-FAN MAKERS. 187 



(i). The spicules (he calls them sclerites, to distin- 

 guish them from the spicules of sponges) have two- 

 small circles of tubercles at a distance from one 

 another on a short axis ; the tuberculate extremities 

 resemble a small branch of cauliflower. This kind is 

 found in the common red coral. 



(2). These spicules are spindle-shaped, with four or 

 six circlets of tubercles. 



(3). In the clubbed spicules a single extremity is 

 dilated, and furnished with ridges like some ancient 

 maces. 



(4). The muricated spicules have four or several 

 points, and entirely covered with spines. 



(5). The last form consists of larger or smaller 

 scales, more or less covered with small spines. 1 



He comes to the conclusion that although useful 

 in the characters of the different species, yet that 

 these spicules cannot be employed for the distin- 

 guishing of one genus from another, because more 

 than one kind of spicule occurs in the same genus. 



Milne-Edwards, and after him, Kolliker, succeeded 

 to Valenciennes, and brought nearer to perfection what 

 he had commenced, especially in the matter of classifi-, 

 cation. The most noteworthy direction in which Kol- 

 liker diverged from Valenciennes, appears to be the 



1 "Abstract of Monograph of Gorgonidae," by M. Valen- 

 ciennes, in "Annals of Natural History," vol. xvi. (1855) p. 177. 



