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posterior side extremely short and sloping downwards, without any of the angularity which characterizes M. bidentata; in front gently curved; on the anterior side considerably expanding and rounded; on the back rising towards the anterior end: beaks small, calyciform, blunt and prominent, incurved, but not having any indentation below them; they are placed close to the posterior side, which is the shortest and not one-sixth the size of the anterior side: hinge-line rectangular, occupying about one-third of the circumference: cartilage as in M. bidentata: hinge-plate narrow and strong, thicker in the middle, not excavated so deeply as in the last-named species, and scarcely at all in the right valve: teeth, in the right valve short, triangular, slightly inclining inwards, not widely separated; in the left valve long, erect, laminar, and parallel with the hinge-line; the anterior teeth are the largest in both valves: inside iridescent and polished, very finely marked (more distinctly on the anterior side) with slight lines which radiate from the beaks: scars irregularly oblong, conspicuous. L. 0-075. B. 0.1. HABITAT. Muddy ground in the Minch, off the north-west coast of Rossshire, in 50-60 fathoms. I there found only a single dead specimen; but twenty years ago I dredged another in Skye, which I deferred noticing until quite satisfied of its differing from M. bidentata. [Since this Report was presented, Mr. Dawson has found two more specimens in some of the dredged sand which I had sent him.] Among the shells procured by Professor Lilljeborg in Bohuslän, on the south coast of Sweden, I observed two or three specimens of the present species, one of which he kindly gave me.

This shell is smaller than M. bidentata; it may also be distinguished from that species by its narrower shape, being convex instead of compressed, having a glossy surface, and by the posterior side being extremely small, with almost a perpendicular truncation. That side in M. bidentata is invariably squarish, and more or less angulated. The teeth in the right valve of M. tumidula are much smaller, and less widely separated by the cartilage-pit; they are triangular instead of leaf-like, and slightly incline inwards instead of being erect.

M. truncata of Searles Wood, from the Coralline Crag, is a comparatively large, squarish, and flattened shell, and has long cardinal teeth.

Report of the Committee appointed for the purpose of Exploring the Coasts of the Hebrides by means of the Dredge.-Part II. On the Crustacea, Echinodermata, Polyzoa, Actinozoa, and Hydrozoa. By the Rev. ALFRED MERLE NORMAN, M.A.

Mr. JEFFREYS having, in his Report upon the Mollusca, already given to the Association an account of the district investigated by the Committee, and of the scope of their dredging-operations, it is unnecessary that I should add more on that subject; and I shall therefore proceed at once to lay before you a brief summary of the results of the dredging with respect to the Crustacea, Echinodermata, Polyzoa, and Cœlenterata.

Although the Hebridean seas had been frequently dredged by the naturalists who were well acquainted with the Mollusca, they had been scarcely at all examined by any one conversant with the other branches of the marine invertebrate fauna; and the result of the recent investigations has thus been most important. This will be at once evident when it is stated that, in addi

tion to the knowledge which has been gained in the extension of the range of many rare and local species, not less than seventy-two species are in the present Report for the first time announced as members of the British fauna. These additions to our lists include 63 species of Crustacea [Macroura 1, Stomapoda 2, Amphipoda 8, Isopoda 1, Cladocera 1, Ostracoda 37, Copepoda 13], 6 of Polyzoa, 1 of Actinozoa, and 2 of Hydrozoa *.

The Crustacea obtained number two hundred and twelve species. Among them were two well-known southern forms, Xantho florida and Xantho rivulosa, which we little expected to find so far north; the latter, however, has been met with by Prof. Lovén in Sweden, though neither had previously been found on any part of the Scotch coast. They occurred in company between tidemarks at Tobermory, and X. rivulosa was also found at Oban. Another southern species, Crangon sculptus, which had not before been found north of Arran in Ireland, was dredged in the Minch; and with it was associated Crangon serratus, Norman, described by me at the British Association Meeting in 1861, from two specimens procured on the Haaf off Shetland. This species had not again been taken in our seas until the present time; but it has been redescribed by Professor Sars, from the Norwegian coast, under the name of Crangon echinulatus †. An Hippolyte, also dredged in the Minch, appears to be an undescribed species. It approaches to H. turgida of Kröyer‡, but differs in many particulars, and especially in the telson, which has no less than nine pairs of lateral spines, and terminates in thirteen spines, of which the nine central are subequal in length and ciliated on both margins. Doryphorus Gordoni (Bate), which has hitherto been regarded as very rare, occurred in abundance. Of the Cumacea there were found two species, recently added to our fauna, Diastylis bispinosa, Say (=D. bicornis, Bate), and Endorella (Endora) emarginata, Kröyer, together with two new forms, one a Diastylis allied to D. biplicata, G. O. Sars, the other a new Iphithoe, which has a crest of from 13 to 20 spines on the dorsal line of the carapace.

Several Norwegian Amphipoda, including some genera of great interest, were for the first time met with in our seas, namely, Ampelisca carinata, Bruzelius, A. macrocephala, Lilljeborg, and A. tenuicornis, Lilljeborg, Eriopis elongata, Bruzelius, and Mæra Lovéni, Bruzelius. There were also found an undescribed Anonyx, and two forms which it is impossible to assign to any genera which have been hitherto established; for these I propose the names Euonyx chelatus and Microprotopus maculatus. The genus Euonyx is allied to Anonyx, but is distinguished by having the first pair of gnathopods furnished with distinct chelæ, and the second pair more strongly formed than the first, with a well-developed subchelate hand. This is a parasitic species living on Echinus esculentus. Microprotopus is allied to Microdeuteropus, but has the first gnathopod feeble, the second largely developed in the male, and subchelate, and the last uropods single-branched.

Three parasitic Isopoda were taken-Gyge Hippolytes, Kröyer, Phryxus

―, sp.,

* If to these we add Montacuta tumidula, n. sp., described in Mr. Jeffreys's Report, and the Foraminifera enumerated by Mr. H. B. Brady as occurring for the first time in our seas, viz. Lagena Jeffreysii, H. B. Brady, n. sp., L. Lyellii, Sequenza, L. pulchella, H. B. Brady, n. sp., L. gracillima, Sequenza, L. crenata, Parker and Jones, Polytrema Haverina compressa, D'Orb., Trochammina squamata, Parker and Jones, T. gordialis, Parker and Jones, Valvulina conica, D'Orb., Cristallaria cultrata, Montfort, and Marginulina raphanus, L., we have a sum total of eighty-five species added to the British Fauna in this expedition.

+ Sars, Vid. Selsk. Forh. i. Christiania, 1861, p. 186.

Monographisk. Frems, Slægten Hippolytes Nordiske Arter, 1842, p. 100.

abdominalis, Kröyer, and Pleurocrypta Galatheæ, Hesse: the first was found under the carapace of Doryphorus Gordoni; the second under the abdomen of Hippolyte securifrons, Norman, and H. pusiola, Kröyer; and the Pleurocrypta was buried under the carapace of Galathea intermedia, Kröyer (= G. dispersa, Bate).

Ostracoda were obtained in extraordinary abundance, and included no less than sixty-five species. This number will, perhaps, be the more appreciated if I refer to the fact that the total number of forms of this order of the Crustacea described in Baird's History of British Entomostraca' only amounts to nineteen. Mr. G. S. Brady, who is engaged in preparing a monograph of these bivalve Crustacea, will present a separate report on the species met with; but I may here mention that thirty-seven are either wholly new to science, or, what is still more interesting, species previously known as Tertiary and post-Tertiary Fossils, and now for the first time met with in a recent state, or such as have been described by Norwegian naturalists from the Scandinavian seas.

A number of Copepoda recently described by Claus, were also met with. These include many genera which were previously unrecognized in our fauna : -the genus Dactylopus, represented by tisboides, Stræmii, tenuicornis, cinctus, and brevicornis; Thalestris, embracing mysis, Helgolandica, harpacticoides, and longimana; Longipedia coronata (a very curious and interesting form), Eupelte gracilis, Cleta serrata, and Porcellidium fimbriatum and dentatum. At Tobermory was discovered Dyspontius striatus, Thorell, a very remarkable genus with an enormously developed proboscis, which is almost equal in length to the rest of the animal.

A small freshwater loch near Stornoway contained, among other species, Drepanothrix hamata, G. O. Sars, a genus allied to Macrothrix, which may be at once distinguished from all allies by the presence of a largely developed spine in the middle of the dorsal margin of the carapace. It is now first announced as British, but has been previously taken by myself in Darden Loch, Northumberland, and by Mr. G. S. Brady in St. Mary's Loch, Selkirkshire.

The Echinoderms number thirty-four species. In addition to the common Antedon rosaceus, Linck, Antedon Celticus of Barrett was procured in deep water, both in the Minch and in Sleat Sound. This very fine species was previously only known to us from the two type specimens dredged by Messrs. MacAndrew and Barrett ten years ago in the Sound of Skye, and described in the Annals of Natural History'*. It is the largest member of the genus found in our seas, and is distinguished at a glance from rosaceus, Milleri, and Sarsii by the great length of the slender dorsal filaments, and also by the vertical position which the arms assume. In this peculiarity it resembles Antedon Eschrichtii, but differs from the other English species, in which the arms are always carried horizontally, or nearly so, and are incapable of being brought into contact with each other throughout their entire length. Only a few specimens were met with in Sleat Sound, and these were associated with A. rosaceus. In the Minch A. Celticus occurred gregariously, living in about sixty fathoms, in company with another rare British Echinoderm, Holothuria intestinalis, Ascanius. The only previously known British example of this species was procured many years ago by Professor Forbes

* Comatula Woodwardii, Barrett (Ann. Nat. Hist. 2nd series, vol. xix. p. 33, pl. 7. fig. 1), Comatula Celtica, Barrett (Ann. Nat. Hist. 2nd series, vol. xx. p. 44), Antedon Celticus, Norman (Ann. Nat. Hist. 3rd series, vol. xv. p. 104).

† Trans. Roy. Soc. Edinb. vol. xx. p. 309, pl. 9. fig. 1.

near the same spot; and as his figure and descriptiont were scarcely sufficient for positive identification, the rediscovery of this Holothurian is important. As among the rarer of the other Echinodermata which were obtained may be mentioned Psolus phantapus, Thyone fusus, and raphanus, Thyonidium commune young (?), and hyalinum, Cucumaria lactea, fusiformis, and Hyndmanni, Brissopsis lyrifera, Asterias hispida, Porania pulvillus, Ophiura affinis, and Amphiura Ballii, filiformis, and Chiajii.

The Polyzoa include sixty-six species. In the Appendix will be found descriptions of many new forms :-a Scrupocellaria differing from S. scruposa in having larger cells, which do not bear any spines, in the proportionately larger vibracular capsules, and in the form of the mandible of the avicularium, which is blunter and shorter; a Lepralia, allied to the incrusting Lepralia-like state of Eschara Landsborovii; another remarkable on account of its much elevated collar-like peristome; a new Eschara, and an Alecto allied to A. dilatans. There is also an undescribed Alcyonidium: but the species of this genus are very difficult; and not having examined the present form in a living state, I have not attempted to define it. One or two small fragments of Brettia pellucida, Dyster, give a second locality for this Polyzoan, at a considerable distance from Tenby, where the type was found. Several rare northern Polyzoa, which had not previously occurred to the south of Shetland, are now traced southwards to the Minch-Caberea Ellisii, Fleming, Lepralia polita, Norman, Lepralia laqueata, Norman, Idmonea Atlantica, Forbes, Hornera borealis, Busk, &c.; and on the other hand we were greatly surprised by the well-known Eschara foliacea turning up in this northern locality, since it is an essentially southern species, which has not previously, I believe, been noticed to the north of Cape Clear.

Turning to the Actinozoa, the neighbourhood of Skye is the well-known habitat of Pavonaria quadrangularis, although the only place which produced it during the recent dredging was Loch Alsh. The rediscovery of Rhizoxenia agglomerata, Forbes *-although a mere fragment was obtained-is well worthy of special mention; but perhaps the most interesting of all the results of the expedition is the occurrence of a second species of Pennatula in our seas, which will be described by Mr. Alder under the name of Pennatula mollis.

The Hydrozoa are not numerous, amounting to only thirty-two species. Sertularia alata, Hincks, and Calicella fastigiata, Alder, had up to the present time been regarded as peculiar to Shetland; the little Sertularia fusiformis, Hincks, and the pretty Plumularia tubulifera, Hincks, not known previously on the Scotch coast, have now their range considerably extended northwards; and in the Appendix there are characters of two Halecia, new to science, one of which, Halecium geniculatum, is remarkable on account of its flexuous hydrosoma, which is bent alternately right and left between the hydrothecæ, and on account of the great length of the simple tubular hydrothecæ; the other, Halecium sessile, may be distinguished by its very small and perfectly sessile hydrothecæ, and by the very large non-retractile polypites.

The Sponges have not as yet been determined. It is, however, worthy of mention that three species peculiarly characteristic of the Haaf of the Shetland seas were living in the Minch, enjoying the companionship of many other of their northern friends. These species were Tethea cranium, Müller, Isodictya infundibuliformis, Linn., and Phakellia ventilabrum, Linn.

Appended will be found a catalogue of all the species found, descriptions * Sarcodictyon agglomerata, Forbes, Trans. Roy. Soc. Edin. vol. xx. p. 309, pl. 9. fig. 3.

of such as are new to science, and a list of all those which are now for the first time recorded as living in our seas, with references to the several authors by whom they have been described.

Stenorhynchus longirostris, Fabr.

Inachus Dorsettensis, Penn.
leptochira, Leach.

Hyas coarctata, Leach.
Eurynome aspera, Penn.
Xantho florida, Leach.
rivulosa, Risso.

Cancer pagurus, Linn.
Carcinus mænas, Linn.
Portunus puber, Linn.
depurator, Linn.
holsatus, Fabr.
pusillus, Leach.

Ebalia tuberosa, Penn.
Cranchii, Leach.

Atelecyclus septemdentatus, Mont.
Pagurus Bernhardus, Linn.
Prideauxii, Leach.
pubescens, Kröyer.
lævis, Thomp.

Porcellana platycheles, Penn.
longicornis, Linn.

Galathea squamifera, Leach.
intermedia, Kröyer.
Andrewsii, Kin.
Munida Bamffia, Penn.
Crangon vulgaris, Linn.
Allmani, Kin.
sculptus, Bell.
nanus, Kröyer.
serratus, Norman

(= echinulatus, Sars).
spinosus, Leach.

Hippolyte varians, Leach.
pusiola, Kröyer.

securifrons, Norman.
cultellata, Norman, n. sp.
pandaliformis, Bell.

Pandalus annulicornis, Leach.

brevirostris, Rathke. Doryphorus Gordoni, Bate. Mysis flexuosa, Müller.

vulgaris, Thomp.

Diastylis bispinosa, Say

Crustacea.

(= D. bicornis, Bate), lamellata, Norman, n. sp. Eudorella* emarginata, Kröyer (=Cyrianassa ciliata, Norman, 3).

Iphithoë serrata, Norman, n. sp.
Talitrus locusta, Linn.
Orchestia littorea, Mont.

Montagua marina, Bate.

Lysianassa Costa, M.-Edw.

Audouiniana, Bate.

Anonyx Holböllii, Kröyer

(= A. denticulatus, Bate),

[blocks in formation]

The name Eudorella is here proposed as a substitute for Eudora of Bate, the latter name having long been employed by Péron and Lesueur for a genus of Hydrozoa.

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