REPORT ON THE POLYZOA. 
31 
1. Alcyonidium. 
Alcyonidium, Lamx., Johnst., Couch, Busk, Engl. Cyclop., art. Polyz.; Hincks, &c. 
Alcyonium (pars), Linne, Pallas, Muller, Fleming, &c. 
Halodactylus, Earre, v. Beneden. 
Cycloum and Sarchochitum, Hassall. 
Character . — Zooecia immersed or subimmersed. Orifice usually papilkeform, more 
or less exsertile. Zoarium erect and lobate or crustaceous or repent. 
(l) Alcyonidium Jlustroides, n. sp. (PI. X. figs. 13, 14). 
Character . — Zoarium erect and foliaceous, much branched, extending to 4 or 5 
inches ; bilaminate, compressed and flustroid. Zooecia 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. ; zooecia irregular 
in size, from about 0'8 x0'4 mm. to l’6x0 - 6 mm. 
Habitat . — Station 142, lat. 35° 4' S., long. 18° 3 7 ' 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 “ brown 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, 1 but entirely differs from that form in 
its erect bilaminate mode of growth. 
1 Brit. Mar. Polyz., p. 498, pi. lxx. figs. 2, 3. 
