FISHES In the latest list of marine fishes of the Irish Sea — that of Herdman and Dawson^ — 141 species are recorded, and owing to the amount of investigation that has been carried out, both on the English and Irish sides of the Irish Sea, this list is most probably a nearly exhaustive one. The present list, however, includes only those fishes which have actually been recorded from Lancashire shore waters, and from the sea within the 20-fathom line off the coast. Too much, however, may be made of these niceties of zoological distribution, and the differences between the piscine faunas of, say, Cumberland, Lancashire, and Cheshire are no doubt due merely to the fact that none of these areas has been thoroughly investigated. Taking wider areas we find that Fries, Ekstrom, and Sundevall, in their History of Scandinavian Fishes, Sauvage and Giard in the Catalogue des Poissons du Boulonnais, and Day in his British Fishes, give what are practically the same lists of marine fishes. The slight differences that exist between the three north-west English counties will no doubt disappear on long-continued investigation. Thus both the Bonito, Thynnus pelamys (Linn.), and the Sword-fish, Xiphias gladius,lAnn., have been recorded from the coast of Cumberland, and the former has been taken off the Isle of Man, while the latter has been caught in the Bristol Channel. Nevertheless, neither has been, so far as I am aware, observed in strictly Lancashire waters. But in respect of the abundance and sizes of fishes very considerable differences do exist even between such adjacent coastal waters as those of Lancashire and Cumberland. In the Solway Firth, it is true, we do find a fish fauna which resembles that of the Lancashire coast, but the Cumberland coast in its southern portion is not characterized by that abundance of very small fishes which we find in Lancashire waters. The greater part of the latter is indeed a ' fish nursery ' on a gigantic scale. This is particularly the case with regard to three great areas — the shallow water off the mouth of the Mersey, the Ribble channels and their vicinity, and a great portion of Morecambe Bay. On these grounds we find all through the year immense numbers of small pleuronectid fishes, principally dabs, plaice, flounders, soles, solenettes, and others. The cause of this remarkable segregation of immature fishes is to be sought in the peculiar physical conditions which obtain off the coast of Lancashire. The set of the tides is such as to convey small floating objects from the offshore grounds and from the deep water off Carnarvon and Cardigan bays into the shallow water on the coast of Lancashire, and to a less extent that of Cumberland. This has been proved by the ' drift-bottle ' experiments made by the Lancashire Sea Fishery Committee, and it is familiar to coasters and others who are generally on the look out on the north Lancashire and Cumberland coasts for wreckage in the case of vessels which break up off Holyhead or off the Mersey. Now the deep water off the coasts of Lancashire and Wales is frequented by mature pleuronectid and 1 Fishes and Fisheries of the Irish Sea; Lancashire Sea Fisheries Memoir, No. 2. London : Geo. Philip and Son, 1902. 179
