HARDWICKE'S SCIENCE-GOSSIP. 



=57 



mutation recorded from Stourport, very similar in 

 colour to the Italian vzx.fiorentitius, Less, and Poll. 



19. A. Itzvis, mut maadatus, Ckll. A spotted 

 mutation, first described from Surrey, but probably 

 common in many places both in England and abroad. 

 No spotted form is recorded in Dr. Scharff's " Slugs 

 of Ireland ; " but the Italian type, as described by 

 Lessona and Pollonera, is spotted. In various parts 

 of the world are found slugs very closely allied to 

 Itzvis, and these are often spotted. A. campestris, 

 Binn., of the United States, is described as without 

 spots or markings, but Mr. W. G. Binney sent me 

 a mottled form from Burlington, New Jersey ; and 

 a dark variety sent by Mr. R. E. C. Stearns from 

 Washington, D.C., has the mantle mottled. In the 

 race montanus, Ingersoll, from the Rocky Mountains, 

 the mottling is obscure or obsolete, and so also with 

 the race hyperboreus, Westerl., from the Pacific Coast ; 

 but the A. berendti, S. and P., found further south, 

 has a var. pictus, Ckll., from Lower California, in 

 which the mantle is spotted and blotched with black. 

 In Bermuda and Jamaica is found a variety of A. 

 campestris, in which the mantle is marbled. 



AllALIA (Moq.). 



20. A. gagates, var. rava, Wilms. A drab-coloured 

 race of the northern subsp. plumbea, Moq. Found 

 in the west of England, and also recorded from 

 Middlesex ("J. of Conch.," 1891, p. 39S), and 

 figured from an Irish specimen by Scharff. Not 

 noticed on the continent, but the mut. olivacea, 

 Moq., found in France and Italy is very similar, and 

 no doubt intergrades with it. 



21. 22, 23, 24. A. Sowerbyi, var. nigrescens, 

 Roeb., mut. rustica, Roeb., mut. fuscocarinata, Ckll., 

 and mut. bicolor, Ckll. Concerning these see " An. 

 Mag. N. Hist.," Oct. 1S90, p. 284; to the account 

 there given may be added, that var. nigrescens does 

 not always lack the internal shell, and that mut. 

 rustica is from Gloucestershire. Of these forms, 

 none of which are known from the continent, bicolor 

 has strong contrasting black and orange colours ; 

 while fuscocarinata is quite the reverse, being of the 

 typical brown, without even the keel differently 

 coloured. Mut. rustica is grey, analogous to the mut. 

 griseus of L. flavus ; and var. nigrescens is strongly 

 melanic. The last, from the London district, comes 

 nearest to being a distinct race. 



ARION (Fer.). 

 25, 26, 27. A. ater, mut. brunneopallescens , Roeb. ; 

 mut. luteopallescens, Roeb. ; and mut. fuscolutescens, 

 CklL These are best considered subvarieties of 

 Moquin-Tandon's pallescens, which is found in 

 France. This grades into the form known as 

 succineus, with varying shades of colour, apparently 

 of no great importance. I formerly considered 

 fuscolutescens identical with a variety described by 

 Baron Paiva from Madeira, but it is possible that his 



slug may really have belonged to A. lusitanicus, 

 Mab., which, according to Simroth, inhabits that 

 island. 



Taking the pale yellowish and brownish varieties 

 of A. ater altogether, their distribution presents 

 features of interest. Dr. Scharff does not seem to 

 have met with them at all in Ireland (" Slugs of 

 Ireland," p. 537). In Scotland they seem to be rare, 

 as Roebuck ("Proc. Roy. Phys. Soc," 1891) records 

 var. pallescens from only two counties, and var. 

 succineus from only two, while the blackish form 

 nigrescens is recorded from seven, and the dark 

 brown brunnea from four. In England, at least in 

 the south-east, they become frequent ; Dr. Leach 

 (" Moll, of G. B.," 1S20, p. 67) included them under 

 his var. 5, which he said was confined to chalky 

 districts, mentioning especially the neighbourhood 

 of Dartford. 



2S. A. ater, var. albolateralis, Roeb. Back black, 

 sides white, the two colours sharply defined from one 

 another ; foot-fringe orange. A most beautiful and 

 remarkable variety, characteristic of North Wales 

 and the Isle of Man, but not known, so far as I can 

 learn, from the continent. Had it occurred out of 

 our islands, it could hardly have escaped notice.* 

 In Ireland it seems to be unknown ; although Dr. 

 Scharff records a form "black with yellow sides," 

 which, however, must be considered nearer to var. 

 bicolor, Moq., than to albolateralis : In Scotland it has 

 been recorded by Roebuck from Sutherland. f 



29. 30, 31. A. ater, mut. plumbeus, Roeb. ; mut. 

 seminiger, Ckll. and mut. cinerascens, Ckll. ( = cincrea 

 Roeb., not Westerl.). These are merely dark muta- 

 tions, the first lead-colour with the margin dull yellow, 

 the second with a dark brown mantle and black body, 

 and the third very dark slate, with a dark brown 

 margin. They may be regarded as forms of razou- 

 mcnvskii (Kal.), which is well known both in Britain 

 and on the continent. The form plumbea is on record 

 for England, Scotland, and Ireland; but the other 

 two only for England. 



32. A. ater, mut. brunneus, Roel. Simply a dark 

 brown mutation of the widely-spread var. rufus 

 (Linn.), but interesting, as showing the tendency of 

 the British forms to become dark. There seems to be 

 every gradation between the bright red form lamarckii 

 (Kal.) and the dark brown brunneus, but while the 

 bright red slug, so common in many parts of the 

 continent, is apparently quite wanting in Briton,! 

 we have the dark brunneus in great abundance. It 

 is common in Englnad ; and in Ireland is recorded 

 by Messrs. Taylor and Roebuck ("Proc. Roy. Irish 

 Acad.," iv. 673) from more localities than any other 



* Simroth, however, does appear to have found a similar 

 form on the shores of the German Ocean. See Dr. Scharff, 

 "Slugs of Ireland," p. 555. 



f For further particulars concerning this variety, see " Journal 

 of Conchology," 1883, p. 39; 1887, p. 198. 



X See also "Slugs of Ireland," p. 538; "Ann. Mag. Nat. 

 Hist.," March 1387, p. 174. 



