SCIENCE-GOSSIP. 



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Cryptic Colouration in British Clausilia. 

 — Mr. W. H. Webb's observations on this subject 

 are very interesting, but not, I think, too 

 convincing. In cases of this kind we have to show 

 that a species has imitated (in contour or 

 colouration) objects among which it is habitually 

 found. For instance, the larva of Geometra 

 papilionaria always occurs among the catkins of 

 Betula and Corylus which it so well imitates. Now 

 I do not think Clausilia are at all generally found in 

 the situations indicated. Old walls, quarries, etc., 

 are notoriously the favourite haunts of C. rugosa 

 at any rate. If this genus has imitated anything, 

 we expect to find that it has sense enough to live 

 among the objects copied. The shape of the shell 

 is probably of use in enabling the molluscs to creep 

 more easily among the stones and the chinks and 

 crannies of the walls and old trees in which it lives. 

 It seems to find its protection in concealing itself 

 entirely. — Arthur E. Boycott, The Grange, Hereford. 



Extending Range of Lacerta Agilis. — The 

 third and rarest British lizard, Lacerta agilis, is, I 

 think, greatly extending its habitat. Gilbert White 

 mentions seeing bright green lizards near Farnham, 

 in Surrey, which were doubtless males of this 

 species. L. viridis, to which he has been thought 

 to allude, occurs commonly on the Continent and 

 in the Channel Islands ; and Bell gives it as only 

 being found in Britain at Poole. In the " British 

 Museum Catalogue of Lizards" English specimens 

 are only noted as having been obtained from the 

 former localities, and they are given in most other 

 works as the only habitat of- L. agilis. During the 

 summer of last year I examined two specimens of 

 this species caught in Kent, and also heard on good 

 evidence that it is abundant on the Lancashire 

 coast, and of its having been secured also in the 

 neighbourhood of Falmouth, Cornwall. It is 

 possible that L. agilis always inhabited these 

 various localities, but was not observed ; though I 

 think this hardly probable, its markings and 

 colour being so very distinct from the commoner 

 L. vivipara If this is not so, it must either have 

 migrated or been introduced. The best method of 

 settling that question would be to ascertain if it is 

 to be found in any of the intervening counties, 

 which would most probably be the case if the first 

 theory holds good. — Julian T. Pym, Foxwold, 

 Brasted, Kent. 



Spider Crabs. — Brighton has not the reputation 

 of being a good place for hunters after marine 

 creatures ; but even here it is quite possible to 

 collect a number of interesting specimens for the 

 aquarium, although perhaps one may not find any 

 rarities. During the spring tides, one day last 

 August, we came upon several specimens of the 

 four-horned spider crab (Pisa tetradon). This was 

 the first time we had found them here ; Bell gives 

 Brighton as one of the localities for them. They 

 were very sluggish, and covered with huge masses 

 of alga;. On turning the seaweeds over on the 

 rocks we saw them feebly moving their legs, and 



on capturing them they made no attempt to bite. 

 Their slow habits would make them a very easy 

 prey, and probably they would be devoured in 

 great numbers, did they not possess their very 

 effective mode of concealment. Spider-crabs all 

 possess a hairy covering over the shell ; if this 

 consists of simply hairs it only holds slimy sand or 

 mud, but if, as in the present cases, the hairs are 

 barbed they hold firmly to the seaweeds or other 

 organisms which the cunning crab plants over his 

 back, effectively concealing himself from enemies. 

 This costume is changed accordingly to the 

 surroundings of the crab, which has been known to 

 discard a covering of bright seaweed when placed 

 in an aquarium amongst duller forms, and so 

 adapt itself to its new conditions. Although the 

 tank we kept them in was quite small, we often 

 had a good deal of difficulty in discovering our 

 specimens. Though not a lively inhabitant of the 

 aquarium it is an interesting one, but unfortu- 

 nately we did not find it very hardy, none of our 

 specimens living very long. After death, we 

 cleared them and set them, and they made rather 

 effective museum specimens. — Catherine A. W . 

 W inckivorth , 11, Old Steine, Brighton. 



Echinus Norvegicus in Scottish Seas. — 

 When Professor Jeffrey Bell published his Cata- 

 logue of British Echinoderms, in 1892, he gave 

 a record of only three localities in British waters 

 for this sea-urchin. Two of these were off the 

 west of Ireland, and one for " Zeatland." For 

 the latter no definite area is stated, whether it was 

 the Atlantic or North Sea side of the islands. I 

 have great pleasure in adding three other localities 

 to the habitat of this small but interesting echino- 

 derm within our area, which should be recorded. 

 During one of my visits to the trawl-boats at 

 Aberdeen, in April, 1885, my attention was arrested 

 by seeing a few small patchy-red and green-coloured 

 urchins, in the bag end of a trawl net. They were 

 all more or less denuded of their spines. Associated 

 with them were Astronyx leoneni and Funiculina 

 quadrangular is. On enquiry I learned the boat's 

 crew had been fishing between the Long Forties and 

 Great Fisher Banks. This fishing ground is a muddy 

 hollow, 60 fathoms deep, about 100 miles north- 

 east by east of Aberdeen, or, taking the nearest 

 land, 85 miles east of Buchan Ness. In consequence, 

 through the kindness of the crew of the steam 

 line boat " Mayflower," I obtained, in May and 

 June, 1895, the results of several hawls of a dredge 

 from distant fishing grounds. On one occasion, 

 while fishing seventy to eighty miles off East 

 Shetland, they found the dredge-bag quite full of 

 E. norvegicus. Without the least exaggeration there 

 must have been 500 specimens. They unfortunately, 

 while in harbour, met with an accident, and only 

 about a dozen specimens were saved. The depth 

 of water in that locality is from seventy to eighty 

 fathoms, and the bottom appears to be muddy with 

 large boulders. To Mr. Herbert Howell, belongs the 

 credit of finding E. norvegicus farthest south and 

 nearest the British coast in the North Sea. Again 

 in October he brought in four specimens which, 

 he informed me, were brought up with the trawl 

 at a distance of seventy miles east of Aberdeen, in 

 75 fathoms, the bottom being muddy. All the 

 Scottish specimens of this species which I have yet 

 seen belong to the small type described in Professor 

 Bell's work, and by the foregoing notes it appears 

 that they are gregarious in their habits and frequent 

 the deeper parts of the North Sea. — James Simpson, 

 6, North Street, Andrew Street, Aberdeen. 



