UMAX. 17 



L. arborum, Bouchard Chantereaux. 



Back rounded, carinated at tail ; shield wrinkled,, pointed 

 behind ; colour cinereous, striped or mottled with dusky ; upper 

 tentacles much shorter in proportion than those of cinereus. 

 Mucus colourless. 



Plate E. E. E. fig. 2. 



Limax arborum, Bouchard Chantereaux, Mem. Soc. Ag. Boul. 2nd ser. vol. i. 

 p. 164. — Alder, Cat. Moll. Northumb. p. 31. 

 „ arboreus, Clarke, Ann. Nat. Hist. vol. xii. p. 334, pi. 11, f. 4-10. — 

 Brown, 111. Brit. Conch, pi. 68, f. 1, 2 ; and pi. 59, f. 9-13. 

 „ salicetum, Bouillet, Cat. Moll. Auvergne, p. 1 8 ? 



„ marginatus, Muller, Hist. Verm. vol. ii. p. 10? — Macgillivray, IMol. 

 Aberd. p. 78 ? 



The tree-slug bears a considerable resemblance to a 

 small individual of cinereus. But when we compare 

 them closely, many differences become evident, especially 

 the much smaller superior tentacles, and the less pointed 

 posterior margin of the shield. Its head is yellowish, 

 or yellowish-grey, with a dusky, often dark line, down 

 the centre, and two other paler ones passing up the 

 centres or sides of the superior tentacula. There is also 

 a transverse dark band across the forehead. The shield 

 is oblong, and slightly obovate, shortly pointed behind, 

 rather coarsely concentrically wrinkled ; its spiracle is 

 placed farther back than in cinereus ; its colour is yellow 

 or grey, with a central irregular dusky band, and two 

 lateral darker stripes. The back is rounded except to- 

 wards the tail, where it is sharply and wavily carinated ; 

 it is covered with coarse, but rather depressed, slightly 

 carinated and waved wrinkles. Its colour is ashy, or 

 pinkish-grey, or yellowish, with more or less distinct 

 dusky or dark mottled bands down each side, and leaving 



VOL. IV. D 



