170 PLYMOUTH MARINE INVERTEBRATE FAUNA. 



Mewstone 'Amphioxus' Ground. Depth 10-12 ftns. About 

 1| miles to the southward of the Mewstone (off Yeahn Head) is a 

 patch of shell gravel of finer texture than that last described, which is 

 one of the few localities in the Plymouth district where Amphioxus 

 lanceolatus has been found in numbers. The fauna of this shell gravel 

 is limited, but very characteristic. In addition to Ainphioxus, the 

 following are typical species : Anapagurus Icevis and Eupagurus 

 cuanensis, inhabiting chiefly the shells of Turritella communis and 

 Aporrhais 2Jes-2:>eIeca7ii, associated with which Epizoanthus incrustatus 

 is very frequent and the Hydroid Merona cornucopice is often found, 

 especially on the Aporrhais shells; Phascolion stromU, not uncommon 

 living in empty Aporrhais shells ; ^Z>«7m tumefada and E. tuhcrosa, Glyccra 

 lapiditm, and Omiphis conchilega. 



Mewstone ' Echinoderm ' Ground. 2-4 miles south of Mew- 

 stone. Depth 23-24 fms. A few years ago this was one of the 

 most profitable grounds in the neighbourhood on which to shoot a 

 trawl when it was desired to obtain a good collection of invertebrates. 

 Recently it has been almost entirely ruined owing to the amount of 

 mud and refuse tipped upon it by barges from Plymouth and Devon- 

 port. The bottom soil consists of a coarse muddy gravel. The trawl, 

 after a successful haul, will contain large numbers of Echinus csculcnhis, 

 together with a few E. acutus; numbers of Solaster papposus, Buccinum 

 undatum, Eupagurus Bernhardus in Buccinum shells, some carrying 

 Adamsia polypus, others Hydractinia echinata, Eupagurus Prideauxi, 

 with Adamsia palliata ; Pecten opercidaris often in quantity, P. tigerinus 

 not uncommon, and an occasional specimen of P. maximus ; Galathea 

 dispersa, Inachus dorsetiensis, Macropodia longirostris, Ascidiella scahra, 

 a few Asterias glacialis and A. ruhcns, and varying quantities of 

 Sertularella Ga7/i and Ccllaria sinuosa and C. fistidosa, according to 

 the exact position of the haul. 



Inside the ' Echinoderm ' ground, between that ground and Yealm 

 Head, in rather shallower water, there is a stretch of coarse, muddy, 

 gravel ground, which is covered almost exclusively with the brittle- 

 star Ophiotlirixfragilis. A dredge hauled on this ground comes up full 

 of these Echinoderms, a few specimens of large Ophiocoma nigra being 

 mixed with them. 



Fine Sand south of Mewstone. Depths 27-30 fms. From 5 

 to 7 miles south of the Mewstone is a frequently worked trawling 

 ground with a bottom of fine clean sand. The fauna here closely re- 

 sembles that found on the Inner Eddystone Trawling Ground (cf. this 

 Journal, vol. v. p. 389). Characteristic and typical species are: 

 Astropcctcn irregularis, ApJirodite aculeata, Corystcs cassivelaunus, 

 Ophiura ciliaris, Dentalium entalis, Alcyoninm. digitahon attached to 



