REPORT ON THE POLYZOA. '31 



1. Alcyonidium. 



Aleyonidium, Lamx., Johnst., Coucli, Busk, Engl. Cyclop., art. Polyz. ; HLncks, &c 

 Alcyonium (pars), Linue, Pallas, Mliller, Fleming, &c. 

 Halodactijlus, Farre, v. Beneden. 

 Gyeloum and Sarchochitum, Hassall. 



Character. — Zocecia immersed or subimmersed. Orifice usually papillgeform, more 

 or less exsertile. Zoarium erect and lobate or crustaceous or repent. 



(1) Alcyonidium Jlustroides, n. sp. (PL X. figs. 13, 14). 



Character. — Zoarium erect and foliaceous, much branched, extending to 4 or 5 

 inches ; bilaminate, compressed and flustroid. Zocecia polygonal, arranged in irregular 

 longitudinal series, the septa between which are raised and strongly marked. The 

 substance of the walls semigelatinous, irregularly dotted with small black granules. 

 Orifice minute, papillseform, superior. Polypide with about sixteen tentacles. Ova 

 scattered, usually singly, in the zooecia. Width of branches about 4 mm. ; zocecia irregular 

 in size, from about 0"8 x 0'4 mm. to 1'6 x 0'6 mm. 



Habitat. — Station 142, lat. 35° 4' S., long. 18° 37' E., 150 fathoms, green sand. 



This species forms straggling tufts of loosely entwined and sometimes anastomosing 

 branches, which are quite soft and flexible in the upper part, though the stem and lower 

 branches become hard and firm near the base. Sometimes the branches embrace and 

 adhere firmly to some foreign substance, such as worm tubes, &c. The structure is at 

 first sight very obscure, as the substance is very thick and opaque ; immersion for a 

 short time in acid, however, renders it much more transparent and enables the nature of 

 the zooecia to be seen. Many of these contain polypides alone, others polypides and 

 ova together, and others again either " browTi bodies " or scattered ova only. The orifices 

 are very small and often quite obscure. The walls seem to be partly membranous and 

 partly of a semigelatinous nature, irregularly dotted with small black granules which are 

 possibly argillaceous. In the form of the cell and the raised septa this species resembles 

 Alcyonidium mytili, as described by Mr. Hincks,* but entirely difi'ers from that form in 

 its erect bilaminate mode of growth. 



» Brit. Mar. Polyz., p. 498, pi. Ixx. figs. 2, 3. 



