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these lines, in the upper region of the column, there exists a vertical series of conspicuous opaque white spots, which gradually diminish in size and brightness from above downwards. These spots are transversely elongated, except the top one of each series, which is a conspicuous round white spot, and is connected with the next spot below it by a short vertical white line. In this way the two uppermost spots beneath each tentacle are united to form a dumbbell-like mark. I describe these markings in detail, because they are not mentioned in the descriptions of Mediterranean specimens. Their presence suggests the possibility that our northern form may constitute a distinct variety of the species. The disk is whitish and semi-transparent, and marked with

opaque grey radiating streaks of an elongated elliptical form, large and small alternately. The larger streaks arise from the base of the long tentacles, and are produced inwards so as to meet the edge of the stomatodæum ; the smaller streaks correspond with the small tentacles,

but do not extend to the stomatodæum. The tentacles have a colour exactly resembling that of the

disc, except that all their tips are vermilion-orange, like

the column. I have rarely seen the mouth pout outwards, as shewn in

the figures of Andres and Jourdan. The animal in captivity burrows in sand until the lower

half or the whole of the column is buried. The disc is always expanded, except upon continued disturbance, and the tentacles are almost motionless. They seem not to be used for catching prey, or for conveying it to the mouth. The only way in which I have persuaded this individual to feed is by placing a piece of rag-worm directly upon its mouth, when it is slowly and steadily

sucked down. In the shortness and non-prehensile character of the

tentacles this Actinian furnishes a near example of that tendency of these appendages to degenerate in deepwater forms, which was so strikingly illustrated by the collections of H.M.S. Challenger.

а

VERMES.

NEMERTINEA. CARINELLA POLYMORPHA, Renier (sp.) Discovered by Mr. Riches (Jour. M.B.A. ii. 1892, p. 284);

trawled in 25 fathoms off Stoke Point; new to Britain.

CEREBRATULUS AURANTIACUS, Grube.
An individual of this species, which I also record upon

the authority of Mr. Riches, was taken under a stone
between tide-marks in Wembury Bay on June 10th last.
It is new to Britain, the nearest locality from which it
has hitherto been recorded being Rat Island, Herm.

ARCHIANNELIDA. DINOPHILUS TÆNIATUS, Harmer. This new Dinophilus has been thoroughly described by

Mr. Harmer in the Journal of the M. B. A. i. 1889, pp. 119-142, plates ix. and x. It is a little worm, not exceeding two millimetres in length, of a bright orange colour; and is abundant at Plymouth in the spring and early summer, in rock-pools near high watermark, immediately below the laboratory and in Cawsand Bay. It is easily seen, in spite of its minuteness, owing to its habit of gliding among the fronds of green confervæ which line the sides of the pools. It consists of a head, five body-segments, and a short conical tail. The head and body-segments are each provided with two rings of cilia. The ventral surface of the body, however, is uniformly ciliated. The second cephalic circlet of cilia, which is entirely in front of the mouth, has a very close resemblance, according to Mr. Harmer, with the præoral ciliated band of a Trochosphere larva.

CHÆTOPODA. STAUROCEPHALUS RUBROVITTATUS, Oersted. I found several specimens of this remarkable little Poly

chæte on June 15th last, dredged in fifteen fathoms, off Stoke Point. Hitherto, I believe, the species has been exclusively found in the Mediterranean, the nearest recorded locality being Marseilles.

CHÆTOGNATHA. SPADELLA CEPHALOPTERA, Langerhans. A littoral Spadella, probably identical with this species,

has been taken several times among algæ in tide-pools in Wembury Bay, and is here first recorded as a member of the British fauna,

POLYZOA. CRISIA RAMOSA, Harmer. This new species was fully described by Mr. Harmer in the

Quarterly Journal of Microscopical Science. (xxxiii. 1891, p. 134, pl. xii.) It is the commonest species of Crisia in Plymouth Sound, and yet has hitherto been taken at only one other locality. It grows most luxuriantly in shallow water, attached to stones in four to six fathoms, the average height of well-grown colonies being about 1 inch. The species is most closely allied to C. denticulata, but can be readily distinguished from the latter by the colour of its joints, which are yellow or colourless, never black. The branches of the colony, moreover, are developed in greater numbers than in any other British species of the genus, and are arranged in fanshaped systems. The ovicell is very large, and is more regularly pear-shaped than in any other species; its aperture is circular, and is borne on a long and very conspicuous funnel-shaped tube, which is considerably wider at its summit than at its base.

MOLLUSCA

OPISTHOBRANCHIATA. HANCOCKIA EUDACTYLOTA, Gosse. My friend, Mr. A. R. Hunt, of Torquay, was the discoverer

of this highly-interesting Nudibranch, and his original specimen remained unique, so far as Britain is concerned, until last autumn, when Mr. F. W. Gamble found another individual in Plymouth Sound. (Jour. M. B. A. ii. 1891, p. 193; Ann. Mag. Nat. Hist. 1892, p. 378.) Its re-discovery is very satisfactory; and, curiously enough, occurred only a couple of months after I had visited Tor Bay, and with Mr. Hunt's personal assistance, repeatedly dredged over the original locality in a futile quest for it.

a LOMANOTUS. I have altogether found sixteen specimens belonging to

this puzzling genus, at Plymouth, and one at Dartmouth. Mr. Gamble also discovered one last year at Plymouth. I am very desirous of obtaining as many individuals as possible of this remarkable form, in order to place beyond further doubt the nature of the specific distinctions in the genus, and to complete an account, which I have in hand, of its anatomy and relations. The difficult points which have already been raised will be found discussed in my papers in the Journal of the M. B. A. (vol. i. 1889, p. 185; 1890, p. 426), and in Mr. Gamble's recent paper in the Annals for May.

CEPHALOPODA. OMMASTREPHES EBLANÆ, Ball. Mr. Hoyle has recently re-described this rare Cephalopod,

a specimen of which was sent to him from the neighbourhood by Mr. Cunningham. (Jour. M. B. A. ii. 1891,

p. 189.) ILLEX COINDETI, Vérany. This species, more generally known as Ommastrephes sagit

tatus, has been brought in by trawlers on several occasions. ROSSIA MACROSOMA, Della Chiaje. This is yet another species which I believe has not

hitherto been recorded from our western shores. I
found a perfect specimen among some squid obtained
from the trawlers on June 24th last, of which the
following dimensions were taken ::

Total length from mouth to posterior extremity 9
Maximum length of mantle (dorsal side)
Breadth of head across the eyes .
Maximum breadth of mantle, excluding fins. 5

including fins

8 Length of ventral arms".

6 tentacular arms

13 cm.

cm.

5.6 cm. 3.5 cm.

cm.

cm.

[ocr errors]

cm.

CRUSTACEA. MONSTRILLA.

ENTOMOSTRACA. Mr. Bourne, in his “Notes on the Genus Monstrilla" (Quart.

Jour. Micr. Science, xxx, 1890, p. 565), has recorded the capture of three different species of this anomalous genus at Plymouth, viz., M. rigida (Thompson), M. Dana (Claparède), and M. longispinosa. The last species is new to science, and is described by Mr. Bourne as peculiar in having the first of the two abdominal segments as long as the preceding thoracic segment, and in the possession of a single two-branched genital seta, which is half as long again as the whole body of the animal.

MALACOSTRACA. IDOTEA PARALLELA, Bate and Westwood. I found a single individual of this species of Isopod on

June 8th last, when it was trawled among weeds in shallow water on a sandy bottom. It was inhabiting a small piece of the stem of a dead Zostera, from which it protruded only the anterior portion of its body; and I observed it walk about, with its “house” behind it, exactly like a common Caddis worm. It was of torpid habits, but could swim in the ordinary way when removed from its protecting tube. It is probably an immature individual, for the first pair of legs (pereiopods)

are not at all enlarged. ANTHURA GRACILIS, Montagu. I dredged a specimen on June 29th last in Plymouth

Sound which possesses first antennæ of a form remarkably different from that which was described by Bate and Westwood as typical of the species. They are immense structures for so small and delicate an animal. Their length exceeds that of the head and first segment of the pereion together; and the flagellum consists of nine joints, each of which is provided with a dense

circlet of long hairs near its distal extremity. I believe that the specimen whose peculiarities I have

described is the male of Anthura gracilis, and that the description given in the “Sessile-eyed Crustacea” is applicable in its entirety only to female individuals of the species. I have compared my specimen with two individuals in a collection of the late Mr. Spence Bate which is now under our charge at the Plymouth laboratory, and I find a very close agreement in all points except those which have been enumerated, and which are probably therefore sexual,

CHORDATA ACRANIA.

ENTEROPNEUSTA. BALANOGLOSSUS SALMONEUS, Giard. An imperfect individual, probably belonging to this species,

was dredged inside the east end of the great breakwater, on July 31st, 1889, the only capture of Bulanoglossus,

I believe, that has yet been made on the British coasts. 1 Since writing the above, I find that the very condition of the antennæ which I have described has been predicted by Norman and Stebbing to occur in adult males of this species. They have described a young male provided with enlarged, although smooth, antennæ, and add: “We think it probable

.. that when quite matured, the antenne would have the flagella even more developed and ciliated.” (Trans. Zool. Soc. xii. 1886, p. 123, pl. xxv.) It should be noticed, however, that the flagellum shown in their figure iii. D), consists of twice as many joints as does the flagellum in my specimen ; but this may possibly have been due to a slight error in the drawing.

In another rather larger specimen since obtained (5 mm, in length) the flagella are 12-jointed, and the antennæ are as long as the head and first two segments of the pereion.

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