EASTERN COAST OF THE UNITED STATES. 



9 



more or less conical, covered with large calcareous imbricated spicula, which appear exter- 

 nally when dry. 



Muricea elegans Agassiz, MS. 



Trunk large, erect, subcylindrical, somewhat compressed transversely, giving off from 

 its sides in a pinnate manner numerous irregular branches, many of which are again ir- 

 regularly pinnate, others simple or forked ; branchlets very numerous, moderately thick, 

 curved, often pendulous, from one to two inches in length. The cells are numerous 

 but not crowded, prominent, compressed-conical, pointed, not appressed, equal in length 

 to about one half the diameter of the branchlets, covered externally with large, imbri- 

 cated, fusiform spicula, which are granulated over their whole surface. Between the 

 cells there are still larger spicula placed in a longitudinal or oblique position along the 

 branchlets at the surface of the coenenchyma. 



Color of dried specimens brownish orange ; axis black, yellow at the ends. Height of 

 the largest specimen, 22 inches; diameter of trunk, .75 of an inch; of branchlets, .17. 

 (Coll. Mus. Comp. Zool.) 



Charleston, S. C, off the bar (L. Agassiz). 



This species is readily distinguished from either of the four species found about the 

 Florida Reefs by its mode of growth, all the latter being dichotomous, as well as by the 

 form and arrangement of the cells. In the last character M. elongata Lamx. and M. laxa 

 Verr. resemble it most, but the first has smaller, more crowded, and appressed cells, while 

 the last has much longer and more pointed ones. 



Family Primnoace^e Milne-Edwards. 



Gorgonince [pars) Ehrenberg, Dana, etc. Primnoacece (pars) Milne-Edwards, Coralliaires 

 (1857). 



Corallum simple or branched, with an axis containing a large portion of carbonate of 

 lime, especially towards the base, where it is stony, but horn-like in the smaller branches. 

 Cells very prominent, covered with imbricated, scale-like spicula ; usually movable at the 

 narrowed base. There appear to be no distinct median grooves ; the cells are usually 

 placed equally on all sides of the branches, and often arranged in whorls. 



Genus Primnoa Lamouroux. 



Gorgonia (pars) of earlier authors. Primnoa Lamx., Polyp. Flex. (1816). 



Corallum branched, usually arborescent. Branches covered with irregularly scattered 

 cells, which are bell-shaped, narrow and movable at the base, and protected by large su- 

 perficial scales. 



Primnoa Reseda Verrill. 



Gorqonia Reseda Pallas, Elench. Zooph., p. 204 (1766). Gor<jonia lepadifera Ltnn., ed. xii. vol. i. p. 1289 (1768) ; Ellis and Sol., 

 Esper, Lamarck, and others. Primnoa lepadifera Lamx., Polyp. Flex., p. 442 (1816) ; Blainville, Ehrenberg, Dana, Milne- 

 Edwards, Verrill, Notice of Primnoa from St. George's Bank, Proc. Essex Institute (Feb. 1862). 



Trunk large, arborescent, branching in a dichotomous manner, often very thick and 



MEMOIRS B08T. SOC. NAT. HIST. Vol. I. 3 



