A HISTORY OF LANCASHIRE 



not form a very inviting shore collecting ground. An abundant and varied 

 shore fauna is only to be seen on a coast with rock pools, caves, seavi^eeds, and 

 the Uke. Nowhere on the Lancashire Httoral do we find such conditions. 

 Only here and there by taking advantage of the lowest spring tides do we 

 find shore collecting at' all attractive. But even the ordinary beach, unattrac- 

 tive as it may appear to the casual naturalist, yields a fair abundance of forms 

 , if studied minutely. Thus Dr. Chaster has recorded no less than 150 species 

 of Foraminifera and 140 species of Mollusca from the ordinary beach round 

 Southport. At a few places we do find a shore fauna of considerable interest 

 to the amateur zoologist, and I may give as an instance the shore in the 

 vicinity of the Lancashire Fishery Research Station at Piel in the Barrow 

 Channel. There we have on the one hand the sandy flats with occasional 

 Zostera meadows on which small crustaceans abound, and on the other the 

 ' Scars ' — rough stony ground with seaweed — which are exposed at low 

 spring tides. Mussels, cockles, and periwinkles are of course abundant. 



In association with the former Molluscs we find the extraordinary 

 Trematode Leucithodendrium somateria. Lev., which is the cause of the pearls 

 so abundant in the mussels on the Piel foreshore. This animal, as Dr. 

 H. Lyster Jameson has shown, passes through larval stages in the cockle and 

 mussel, and in the latter becomes encysted and surrounded by the calcareous 

 investment which becomes the pearl. The adult stage of the Trematode is 

 found in the ' Scoter ' or Black Duck, which feeds on the mussel. Other 

 Mollusca are abundant ; oysters are found, though not frequently ; Mytilus 

 modiolus, the horse mussel, is frequently dredged in Barrow Channel ; ' hen 

 pens ' {Mactra, Scrobicularia, and Tellind) may be got alive, and dead valves of 

 the tapestry shell [Tapes), Nucula, the spiny cockle {Gardium echinatum), 

 Psammobia, Donax, and others are numerous. The Clam {Mya arenarid) is 

 quite common, and it often harbours the peculiar commensal Nemertine 

 {Malacobdelld) in its mantle cavity. The whelks Buccinum undatum and Fusus 

 anttquus, the dog whelk [Purpura lapillus), and the limpet [Patella vulgata) 

 are of course abundant. Nudibranchs such as the sea slugs Doris and Eolis 

 are present, and the gelatinous spawn of the former may always be got during 

 the early summer. Cephalopods turn up ; Octopus is often got in the stake 

 nets. Many Crustacea occur, such as the crabs Cancer, Carcinus, Portunus, 

 Hyas, Stenorhynchus, and the hermit Pagurus. The beautiful fairy prawns 

 Hippolyte varians, H. cranchii, H. fascigera, and H. pusiola may be got here in 

 greater abundance than anywhere else in the Irish Sea. These animals are 

 remarkable for the adaptation of their colour markings to that of the seaweeds 

 on which they are found. This form of adaptation has been explained 

 as one of ordinary protective resemblance, but the phenomenon is far from 

 being a simple one. My sis neglecta, a common Schizopod, is extremely abun- 

 dant. At least four genera of Pycnogonids may be collected — Nymphon, 

 Pallene, Ammothea, and Anoplodactylus. Of the Echinoderms, the starfishes or 

 ' crossfishes,' Asterias and Cribella, the Sun star [Solaster), and the urchin 

 [Echinus) may be obtained alive, and dead tests of the heart urchin [Spatangus) 

 and Echinocardium can be picked up. On this side of Morecambe Bay the 

 common starfish has proved itself at times an intolerable nuisance, for many 

 acres of the beach may be literally carpeted with these animals, which can be 

 extremely destructive to the mussel beds. The starfish pulls apart the valves 



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