MARINE ZOOLOGY Lancashire waters, and also the Ctenophores, but the county waters contain relatively few of the zoophytes, and not all the Actinians described. The Siphonophores are Agalmopsis elegans, Sars., and Vehlla pela^ca, Esch. These are to be regarded as visitants only. PLATYHELMINTHES {Flat worms) Thirty-three species of Turbellaria are recorded in the B. A. List of 1896 and in subsequent lists. Most of these have been described from Manx waters, but there can be little doubt that they exist also on the Lancashire coasts, which, in many places, furnish a suitable habitat for these creatures. Trematoda or ' flukes ' are all parasitic in fishes, sea birds, and marine mammalia, larval stages being, however, found in every class of invertebrata. It is only recently that these animals have been worked at, and then only in connexion with the economic investigations of the Lancashire Sea Fisheries Committee. It is mainly because of the great importance that these parasites may possess in connexion with disease that this study has become of such importance. About a dozen ectoparasitic and four or five endoparasitic Trematodes have so far been recorded from fishes caught on the Lancashire coast. This can only be a small fraction of the number of these worms that are no doubt present. Of the ectoparasitic forms, four, Diplectanum ^equans, Diesing, Leucithodendrium somaterics. Lev., Microcotyle labracis, van Ben. and Hesse, and Placunella pint, van Ben. and Hesse, were new to the British fauna when recorded from Lancashire. Cestoda or tapeworms are as yet practically untouched, only about three species having been actually recorded from Lancashire fishes. These are Bothriocephalus punctatus, Tetrarhynchus tetrabothrius, van Ben. and T. erinaceus, van Ben. ECHINODERMATA [Starfishes, etc.) Thirty-five species of Echinoderms are recorded in the B. A. List of 1896. Most of these occur on the Lancashire shores and sea, but the crinoid Antedon, the rosy feather star, is found about Puffin Island on the south and round the Isle of Man. The sea-cucumber, Cucumaria plancei, was first found in Britain in this district. I have seen it in great abundance in Luce Bay, north of the Irish Sea proper. The commonest forms, such as Asterias, Echinus, Solaster, Spatangus, Ophiocoma, and Ophiura, are, however, very abundant. I have known a tow-net gathering taken off the mouth of the Ribble to consist of practically nothing else than the pluteus larvae of some Echinid. ACANTHOCEPHALA This small group of parasitic worms is apparently represented by Echinorhynchus acus only. CHiETOGNATHA Sagitta bipunctata, Quoy and Gaimard, the arrow worm, is the only species recorded from Lancashire ; but I think that other species probably exist and have not been discriminated. NEMERTINEA Twenty-six nemertines are recorded in the B.A. List of 1896. HIRUDINEA [Leeches) The well-known skate-leech, Pontobdella murtcata, and a leech from the angler fish, are the only hirudineans recorded. GEPHYREA Only Thalassetna lankesteri, Herd., and Phascolosoma vulgare, de BL, are recorded, but no doubt other species exist. The former species does not belong to Lancashire waters, being got far out at sea. CHiETOPODA Ninety species of Chaetopods (including the Archiannelids and Myzostomida) are recorded in the B. A. List of 1896. Not all these are recorded from the Lancashire shores, but there is little doubt that the majority are to be found if properly looked for. POLYZOA About 150 species and named varieties are recorded in the B. A. List. 95
