HYDRACTTNIA ECHINATA. 345 



figures of liis genus Ilydractinia, which, however, he mixes up with Podocoryiie} He rephiccs 

 ills former specific names of lacle<t and rosea by Fleming's name of echinafa, while he describes 

 from imperfect data what he regards as three new species of the genus. Whatever these may 

 be, tiiere are no grounds for referring them to Hydradhiia in the sense in which this genus is 

 limited in the present Monograph, though in the wider sense in which it is understood by Van 

 Beneden, they may legitimately 'n\\i\ a place in it. 



1. Hydractixia ECHINATA, Flemhuj . 

 Plate XV, and Plate XVI, figs. 10 and 1 1 . 



Alcyonium ECHiNATUM, — Fleming, British Animals, 1828. Blainville, Actinologie, p. 525. 



Alcyonidrum ECHINATUM,. — Johiiston, British Zooph., 1838, p. 304, pi. xlii, figs. 3, 4. 



CoRYNE sQUAMOs.\, var., — Johnston, British Zooph., 1838, pi. ii, figs. 4, 5. 



Hydractinia, sp., — Van Beneden, Bui. de I'Acad. Roy. de Brux., torn, viii, 1841. 



EciNOCHORiuM CL.wiGERCM, — Hossall, Ann. Nat. Hist., 1841, vol. vii, p. 371, pi. x, fig. 5. 



Dysmosphosa conchicola (?), — PA;///?/ji, Wiegman's Archiv, 1843. 



Synhydra parasites, — De Qnatrefages, Ann. des Sci. Nat., 1843, vol. xx, p. 230, pis. 8, y. 



Hydractinia lactea et H. rosea, — Van Beneden, Rech. sur I'Embryogenie des Tubulaires, 



Mem. de I'Acad. Roy. de Brux., torn, 

 xviii, p. 104, pl. ix. 



Hydractinia ecuinata, — Johnston, Brit. Zooph., 1847, p. 34, pl. i, figs. 4, 5. Strethill Wright, 



Edinb. New Phil. Journ., April, 1857. Van Beneden, 

 Recherches sur la Fauna littorale de Belg., 1866, p. 134, 

 pl. xl, figs. 1 — 8 (exclusive of synonymes). Hincks, 

 Brit. Hydr. Zooph., p. 23, pl. iv. 



TROPHOSOME. — Hydkanths crowded on the surface of the hydkophyton, and 

 attaining a height of about half an inch ; tentacular circlet formed by two or more 

 closely approximated series, the tentacles of the distal series being longer, and when 

 extended carried more erect than those of the proximal series. Cylindrical spirally 

 contractile appendages developed from the common basis of the colony near its 

 margin. Common basal expansion attaining a thickness of about a line and a half, 

 closely set with blunt conical spines which attain a height of about one line, and 

 which are traversed fi-om base to apex by longitudinal jagged ridges. 



GONOSOME. — Blastostyles shorter and thinner than the hydranths ; spoeosacs 

 oval, almost sessile on the blastostyle, near whose distal extremity they are borne in a 

 cluster more or less dense. 



' 'Recli. sur la Fauue lit. de Bels-,' p. 131. 



