234 Mr. W. King on some Shells and other Invertebrate Forms 



or three of the common Cyprina (all of which were odd valves), 

 and a single Scalaria Trevelyaniana : the living objects were one 

 each of Trochus tumidus, Natica grcenlandica, Rimula Noachina 

 and Mysia undata, a few specimens of Chiton cinereus, two or 

 three of Pecten opercularis, half a dozen of Dentalium entalis, a 

 Psolus squamatus (adhering to the inside of a valve of Cyprina 

 islandica), a few young specimens of Psolus phantapus, one of 

 Halichondria mammillaris (growing on a stone), and a new species 

 of Crustacea of the genus JEga . Although very rare, I had pre- 

 viously got from the boats Natica grcenlandica, Halichondria mam- 

 millaris and Psolus squamatus ; the last, as far as I have been 

 able to ascertain, has not been procured on the east coast of Britain 

 before. 



In consequence of the sea being very rough, it was decided not 

 to put the dredge down again until the weather turned more 

 favourable, but in this we were disappointed, as a heavy gale came 

 on which compelled us to run in for the Scotch coast, which 

 together with the Cheviots we saw the next morning, — the sea 

 all the time heaving dreadfully. In the evening (Wednesday), 

 the gale having suddenly abated, we thrice succeeded in putting 

 down the dredge in thirty fathoms, and at about as many miles 

 from the south part of the coast of Northumberland. The prin- 

 cipal objects brought up were Echinoderms, as Ophiura texturata, 

 Luidia fragilissima, Spatangus purpureus, Amphidotus cordatus, 

 along with which were several fine specimens of Nymphon gigan- 

 teum, a few corals and corallines, as Farcimia salicornia, Cellepora 

 Skenei, C. ramulosa, Eudendrium rameum, Tubularia gracilis, 

 Thuiaria thuia, &c, a single living specimen of Pecten striatus, 

 Miiller, two or three of P. opercularis, and several fragments of 

 Sabella lumbricalis (?). As Nymphon gig ant eum is a rare species*, 

 and the Pecten striatus a remarkably fine specimen, and specifically 

 new to our coasts, it may readily be imagined that I was quite con- 

 tent with our evening's operations. The Echinoderms were beau- 

 Forbes that Mya truncata " inhabits the littoral, laminarian and coralline 

 zones on the coast of Great Britain," that is, ranging from between tide- 

 marks to fifty fathoms (vide Memoirs of the Geological Survey, vol. i. pp. 375 

 and 408). Were all the specimens obtained from these zones in a living 

 state? and were they all of the elongated form ? From what I have seen of 

 the variation of Mya truncata on our coasts (vide remarks on the variety 

 M. pelagica), I am led to suspect that the living specimens from the coral- 

 line zone are much shorter than those from shallow water. It is stated by 

 Mr. Lyell that he has intermediate varieties between the normal form of 

 Mya truncata and M. Uddevallensis (vide Geological Transactions, 2nd ser. 

 vol. vi. p. 137) ; it would be arriving at an important point in the history of 

 these species if the depth of habitat of the several varieties here alluded to 

 were known. 



• First described by Mr. H. D. Goodsir in the Reports of the Berwick- 

 shire Naturalists' Club, vol. ii. p. 1 14. [See also this Journal vol. xv. p. 293.] 



