468 ON THE FAUNA AND BOTTOM-DEPOSITS NEAR THE 30-FM. LINE 



Asterias glacialis. 



Geographical. Depth. I Bottom-deposit. 



Eastern side of N. Atlan- 0-98 fathoms. I Rooky and stony 

 tic from Cape Verde to ground, and on 



Finmark. Not found sand. Never on 



in North Sea, Katte- mud. 



gat, and Baltic. 



Mediterranean, generally 

 distributed. 



Arctic Ocean, probably 

 absent. 



Ophiura ciliaris (Chart VIIL). This species has been taken on all 

 the grounds, with the exception of the Prawle Stony Ground (XVIII.) 

 and the fine gravel ground (XV.) It was taken in greatest numbers 

 in the hauls on the gravel and sand, north-west and west of the Eddy- 

 stone (Grounds IX., XI., XII.), and was moderately abundant also on 

 the fine sand of the trawling ground (I. and II.). On the other 

 grounds one or two specimens only were taken in a haul. 



Habits. Ophiura ciliaris is not a Ijurrowing species, Init is capable of moving with con- 

 sideralile rapidity over the surface of the sand or gravel. Hence its distribution does not 

 depend so directly ui>on the texture of the bottom -dejiosit, as in the case of burrowing 

 forms, when once the deposit is sufficiently firm to prevent it sinking, but is probably 

 determined by tlie jiresence of a suitable food-su])ply. The only record I have found of the 

 food of this species is one by the naturalists of the Pommeraniu expedition. Mcibius (No. 

 88) state.? that Prof. Metzger took from the stomach of a specimen dredged in 9 fathoms 

 a Nephthys cocca, which was still alive. In a specimen which I examined from haul 93 

 I found the remains of a small crustacean. 



Distribution. Geographical. Mobius and Blitschli (No. 88) give Norway, Kattegat, 

 Great Britain, France, Mediterranean, and Madeira. A comparison of the distribution of 

 this species with that of 0. alhida is made on p. 469, where the latter species is discussed. 



Depth. Lyman (No. 71) gives the range 5 to 100 fathoms. In the Kattegat Petersen 

 (No. 95) records it once (sta. 180) at 2^ fathoms, once (sta. 47) at 3 fathoms, once at 

 6 fathoms (sta. 132), and it is common in many parts at greater depths to 70 fathoms 

 (sta. 58). Hoyle (No. 52) records the species from 100 fathoms, off St. Kilda, and Koehler 

 (No. 60, Monaco dredgings) from 136 fathoms in the Bay of Biscay. 



Bottom-deposit. Forbes (No. 22) states that this species does not confine itself so much 

 to sandy ground as 0. alhida. Miibins and Butschli (No 88) record it in the North Sea 

 most frequently from fine grey sand, once only from blue mud with some sand. Meissner 

 and Collin (No. 76) in the southern part of the North Sea found it on coarse sand with fine 

 stones, on sand, on sand and mud, on sand and shell, and on mud. In the Kattegat 

 (Petersen, No. 95) it occurs on sand and on sand with mud. It is only recorded once from 

 the pure nuid (sta. 46, depth 49 fathoms). Chadwick (No. 15) records it from a muddy 

 bottom at 10 fathoms in the Menai Straits, associated with great numbers of 0. alhida. It 

 is also recorded from fine sand and broken shell, and from sandy mud in the Irish Sea (No. 

 40, vol. ix. p. 32). The Prince of Monaco obtained 0. ciliaris in the Bay of Biscay at five 

 stations, always on sandy ground (No. 60). Haddon (No. 34) found it off the south-west 

 coast of Ireland in 44-47 fatlioms on mud, and in 35-40 fatlioms on coarse sand. Hoyle 

 (No. 52) found it in Loch Slieildag in 67 fathoms on stiff grey mud. 



Ophiura alhida (Chart IX. ). 0. alhida is much less numerous on the 

 grounds investigated, as well as in the whole of the Plymouth district, 

 than 0. ciliaris, and its distribution is much more restricted. The only 

 ground upon which it was found at all plentifully was the coarse gravel 



