MARINE ZOOLOGY
fish (Liparis montagui), the lump sucker (Cyclopterus lumpus), and others are (some of them at least) always present. A remarkable fish which is always present in more or less abundance is the virulent 'stinger' Trachinus vipera. A huge host of invertebrates is always present. Chief among these is the swimming crab Portunus depurator, and it is remarkable that an unusually large proportion of these are infested with the parasitic cirripede Sacculina. Starfishes (Asterias) are extraordinarily abundant at times, and during the summer months the Medusæ Rhizostoma, Aurelia, and Cyanea are present. Sometimes the former is a great nuisance to the shrimping boats. Large forms, a foot or more in diameter, are so abundant at times as to clog up the net with broken fragments. If these are allowed to dry on the meshes a fine dust is formed when the latter are shaken out which produces most unpleasant effects on the nasal and respiratory epithelia, due no doubt to the dried substance of the nematocysts of the medusas. Other crabs, the shore crab (Carcinus), spider crabs such as Hyas, Stenorhynchus, the hermit crab (Pagurus), and the edible crab (Cancer), are often present. The squid (Loligo) and the cuttle fish (Sepia), mostly young specimens, occur during the autumn. The Ctenophore Pleurobrachia is incredibly abundant at times, being just large enough to be retained by the meshes of the nets. Shrimps and 'sprawns' are found, the former in immense numbers, the latter rarely; and small lobsters are frequently present. Zoophytes are rare.
The above forms may be regarded as fairly representative of the inshore marine fauna of Lancashire waters. The abundance of the fishes varies with the season, but large numbers are always present. As many as 15,000 dabs and 10,000 plaice have been taken on the shallow water grounds off Blackpool. About the middle of June (but the precise season varies) small pleuronectid fishes are extraordinarily abundant. If one walks along the shore about that time, following the receding tide, almost anywhere on the Lancashire coast—say on the shore near the New Brighton Pier—it is possible to observe and collect great numbers of small plaice and dabs in the pools left by the tide. These are then no bigger than the thumbnail. A few weeks later they disappear, having sought deeper water.
Further out at sea, beyond the zone of which I am now treating, the fauna changes somewhat. I may give as an instance a haul with a shrimp trawl near Liverpool Bar, in water of 6 fathoms. On this occasion over 17,000 specimens, belonging to thirty-four genera and thirty-nine species, were identified. The fishes were sole, plaice, dab, cod, whiting, haddock, herring and sprat, skate, ray, goby, 'stinger,' and the 'pogge' (Agonus cataphractus). The Mollusca were the mussel (Mytilus edulis), 'hen pens' (Tellina tenuis and Mactra stultorum), the whelk (Fusus antiquus). The Crustacea were various, swimming crabs (Portunus spp.), the hermit crab (Eupagurus bernhardus), shrimps, Sacculina, several Amphipoda, Copepoda (Longipedia coronata, Ectinosoma spinipes, Sunaristes paguri, Dactylopusia rostrata, Cletodes limicola, Caligus rapax); the sea-mat (Flustra). The polychætes were the sea mouse (Aphrodite), the sand-pipe (Pectinaria), and Nereis; the starfish, Asterias. The zoophytes were Hydractinia echinata, Sertularia abietina, and Hydrallmania falcata. The coelenterates were the Medusæ Aurelia aurita and Cyanea.
Because of the extensive sand and mud flats, the Lancashire coast does
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