UHIVBRSITyll 



SUBORDER A L C Y O N A R I A. Q45 



readily on drying, that certain species are rarely seen in cabinets with 

 the cortex adhering; and the axis resembles much an Antipathes, 

 though distinct in not having a spinulous surface. 



As in the Madreporidae, the retracted polyps are sometimes still pro- 

 minent above the surface, and the branches, in this state, are covered 

 with small verrucse, corresponding to the calicles of a Madrepore. In 

 other species the polyps are wholly retractile, and leave only a small 

 polyp-pore or oscule, marking their position. The one kind pass by 

 insensible gradations into the other. 



The cortex under a magnifier shows numerous minute granules or 

 spicules of lime, disseminated through it. These spicules become 

 exsert in certain of these zoophytes, especially about the verrucse, and 

 give them an echinulate surface ; and in some instances the verrucse 

 appear to be covered with imbricate spinules or scales. 



The Gorgonise may be distributed into three parallel subgenera. The 

 groups pass into one another in many points by insensible gradations ; 

 yet the distinctions are convenient. A farther study of the animals 

 may require a different arrangement; but the characters now known 

 are hardly sufficient to authorize the institution of genera, as proposed 

 by Lamouroux. The subgenera are as follows : 



SCBGEN. 1. PTEROGORGIA. Polyps seriate, or bifarious, with a naked 

 space between the ranges of polyps. 



SUBGEN. II. GORGONIA. Polyps irregularly scattered, not bifarious ; 

 surface of zoophyte, after retraction of polyps, smooth or more or less 

 verrucose, without exsert spicula. 



SUBGEN. III. MURICEA. Polyps irregularly scattered, surface after 

 retraction of polyps verrucose, and verrucse armed with spicula or 

 scales. 



The Gorgoniaa and Pterogorgise, form a parallel series of species, 

 with the cross gradations numerous and close. The Muricese con- 

 stitute a much smaller group, a part related to the Gorgonise, with 

 short verrucae, and others to those with prominent imbricate verrucse. 



The genus Gorgonia was instituted by Linnaeus for all the Gor- 

 goninse. Lamouroux subdivided the group by separating those with 

 a thick smooth cortex, to form the genus Plexaura ; those with pro- 

 minent unarmed verruca?, Eunicea ; those with the verrucse armed 

 with spicula, Muricea ; and those with the verruca? armed with scales, 

 Primnoa; the remainder, with a thin cortex and small verrucse or 

 none, constituted his genus Gorgonia. These genera, excepting.the last 



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