Page:VCH Sussex 1.djvu/125

 MARINE ZOOLOGY LafoEid^ 23. Lafoea dumosa, Fleming. This species occurs in two forms, either with simple stem over-running other coral- lines and giving off, without footstalks, tubular calycles narrowed and slightly twisted at the base; or it is found with compound branching stem giving off around the axis the closely arranged calycles, the whole suggesting perhaps a very prickly bramble in miniature. Both forms common in the coralline zone. Hastings. 24. Lafoea pocillum^ Hincks. Upon Dlphana rosacea, Eudendrlum rameum, etc. The creeping stem gives off short, ringed peduncles with tubular but shapeable calycles, some of which appear to approach to the more tubular form pygmcea. In the Hastings specimens the peduncle has from four to six rings, whereas Hincks gives from five to eight for this species, and two or three to Alder's s^zzt%pygynesa. Some- what rare. Hastings. 25. Lafoea pygmaa (?), Alder MS. Some years ago this species was recorded from Hastings, but in the absence of notes and specimens mislaid, a query is here appended. 26. Caiycelia synnga, Linnaeus. Over-running the polyzoan Anguinella palmata together with Opercularella lacerata, already noticed. The calycles are borne upon short, three-ringed footstalks given off from the creeping unringed stem. They rather resemble those of 0. lacerata, but are longer and not so swollen in the middle. Some of the smaller calycles which have the operculum introverted, and so not seen, bear a resemblance also to the calycles of Lafoia pocillum and pygmcea. Common upon Anguinella at low tide. Hastings. 27. Filtllum serpens, Hassall. Stem nearly always creeping over other hydroids, but in one instance upon a scallop shell. It gives off ovate tubular calycles without footstalk, the lower half being adnate, and the upper half curved upwards, showing a slightly trumpet-shaped aperture. Calycles transversely lined. There is a remarkable form in which apparently this species occurs, not mentioned by another author, so far as the writer is aware, and which merits notice. Upon old shells covered with incrusting polyzoa, the zooecia of the latter will often be found to contain hydroid calycles peeping out of the apertures and bearing nearest resem- blance to the present species. The calycles are always black and glassy, possibly dis- coloured by sulphuretted iiydrogen ; some- times they are long and tubular, at others ovate in the lower, and tubular in the upper half, and always with very trumpet-shaped apertures. There is generally one calycle in each zooecium, but occasionally there are two. On dissolving the zooecia in acid, only imperfect calycles are obtained, show- ing no connection with a stem. It is possible that these may be the primary zooecia of the present species which are prevented from freely budding by reason of their limited surroundings. The type form is common, and the other form described is not uncommon. From deep water. Hastings. CoPPINIIDi^ 28. Coppinia arcta, Dalyell. A peculiar zoophyte, usually found surrounding in short masses the stem of Hydrallmania. A cross-section of the dry polypary shows a chitinous layer enveloping the stem, tunnelled with passages, one above the other. From these passages arise, at a little distance apart, tubular calycles bent in the upper portion at about a right angle. The calycles at half their height are cemented together by a floor of chitine. In the intervening spaces of this floor are seen slightly-tubular orifices, apparently subserving the escape of the planules. Not uncommon. Hastings. Haleciid.* 29. Halecium halicinum, Linnaeus. Rather a coarse looking zoophyte. Stem and main branches compound ; branches given offpinnately ; the footstalks bearing the calycles are telescopic in appearance, the latter resembling in shape a drinking- tumbler. It is important to note in the female gonophores of this genus, as Hincks has pointed out, that the gonozooid-bearing polypites are not atrophied as in all the rest of the Thecaphora, but are perfectly recognizable polypites, protruding from one side of the capsule. From moderate to deep water; common. Hastings. 30. Halecium beanii, Johnston. A species of much more delicate and flexible habit than the last. In the female gonophore there is a lobe which projects considerably in front of the aperture. From deep or moderately deep water ; not un- common. Hastings. 79