GEOMALACUS. 1 1 



tro-lateral. The back and hinder portion of the body 

 are similarly marked in fasciated individuals; in some, 

 they are of an intense blue-black, with little trace of 

 bands ; the surface is covered with oblong slightly cari- 

 nated wrinkles, which are dusky, and mottled with minute 

 white specks. The sides of the foot are pale or white, 

 very narrowly margined at the sole, with plain grey or 

 orange. The tail-margin is lanceolate, not expanded and 

 obtusely pointed. 



This species is, probably, common in gardens through- 

 out the greater part of Britain, though not generally 

 noticed. It is common around London, and equally 

 so, according to Mr. Alder, in Northumberland. It is 

 also frequent in Ireland. 



The eggs of the Arion horiensis are stated by M. 

 Bouchard Chantereaux, to be phosphorescent during the 

 first fifteen days after they have been laid. 



GEOMALACUS, Allman. 



Animal elongated, semicylindrical, dorsally carinated, 

 furnished anteriorly with an ovate disk, in which is 

 imbedded an unguiform shell. Head with four tentacula, 

 the two upper ones furnished with eyes. Respiratory 

 orifice at the anterior margin of the right side of the 

 disk. Reproductive orifice near the base of the right 

 inferior tentacle. 



This remarkable, and very distinct genus diflfers from 

 Arion in the position of the reproductive orifice, and 

 from Limax in the presence of a caudal gland, and the 

 position of the spiracle. As yet a single species only 

 presenting these characters has been found, and that con- 

 fined to the south-west of Ireland. 



