210 I'LYMOUTII MAltlNE IXVEKTEBRATE FAUNA. 



[ Echinoderma— co«(^. ] 

 Ophiotliricidae. 



OnilOTilKiX FKACiLis (0. F. Mullei): E. Forhr.-i, Hist, liiil. Starf., p. 60, 

 tig. (u.s Ophiocoina rosula). 



Generally distributed and enormously abundant at certain 

 stations, L.W.-35 fms. ; a small, solitary, greyish-coloured form 

 occurs under stones on the shore ; in deeper water it grows to 

 a much larger size and is usually very brilliantly coloured ; this 

 latter form favours a coarse gravel ground and lives in such pro- 

 fusion where it occurs that the dredge will frequently come up 

 completely filled with a practically pure gathering of this species 

 alone (s.P.). 



Gonads ripe : Mar.-June (k.a.t.) : Aug.-Sept. (s.P.). Spawning : 



Oct. (R.A.T.). 



Echinidae. 



Echinus acutus, Lamarck : F. J. BcU, Catal. Brit. Echinod. Brit. Mus., 

 p. 146. 



Not uncommon in 15-35 fms., chicily on the finer grounds (E.A.T., 

 S.P.) : more common in deeper water, where it replaces E. csculentus 

 (e.j.a.) : Mewstone Gds. (it.A.T.) : Stoke Pt. Gds. (s.P.) : Eame- 

 Eddystone Gds. (r.a.t., s.p.): Eddystone Gds. (e.j.a., s.p.) : Looe- 

 Eddystone Gds. (s.p.). 



The Voljchxte Siplionostoiiia <fffi)iisis often found associated with 

 this form, crawling among its spines (r.a.t.). 



Breeding in July (w.G.). 



Echinus esculentus, Linnaeus: A. Ayassiz, Illustr. Catal. Mus. Harvard, 

 No. vii, p. 491, fig. 



(Queen's Gd., occasionally; moderately common in 15-35 fms., 

 especially on the Mewstone 'Echinoderm' Gd. ; liame-Eddystone 

 Gds. (r.a.t., s.p.): Eddystone Gds. (e..j.a., s.p.): Mewstone Ledge; 

 Stoke Pt. Gds., common (s.P.) : Cattewater, probably from trawl 

 refuse (r a.t., s.p.). 



The Polycluete Scalesetosus assimilis is often found among the 

 oral spines of this species (k.a.t.). 



Gonads ripe : Mar. (r.a.t.) : May (s.p.). 



Echinus MILIARIS, Linnteus : E. Forbes, Hist. Brit. Starf., p. 161, fig. 



Common under stones at all shore stations, and frequently met 

 with in dredgings, L.W.-35 fms. (s.p.): specs, from the deeper water 

 stations are usually small ; largest ones from Church Peef, Wembury 

 B. (r.a.t.) : Yealm P., very common near the oyster beds (e.j.a.). 



Breeding : May (w.G.). 



Clypeastridse. 



Echinocyamus pusillus (0. F. Midler): F. J. BcU, Catal. Brit. Echinod. 

 Brit. Mus., p. 160, fig. 



Not uncommon on gravel bottom, 10-35 fms. (s.P.): Queen's Gd., 

 occasionally (U.A.T., S.P.) : Mewstone Ledge shell gravel, very 

 occasionally; Mewstone ' Amphioxus' Gd., moderately conmion 

 (r.a.t.) : Eddystone Gds. (e.j.a.). 



