212 COCKERELL AND COLLINGE : CHECK-LIST OF SLUGS. 



pyrenaicus is similar, but the ground-colour is dark grey, 

 niger is so dark as only to leave the ground-colour appearing 

 as pale bands. The form albipes has the sole white 

 (slime colourless), typus has it yellow with the sides of the 

 foot reddish, and in pelophilus the margin is decidedly red. 



385^, pallida, Roeb , Naturalist, Aug. 1887, p. 249, from Lincoln- 

 shire, was not described. Possibly it is the same as 

 v. nemoralis, which is a very pale form, though more or less 

 banded. 



385 //. luteus. This seems to differ from virescens in being yellow, 

 and having less pronounced bands. 



390. A. alpiuus. Poll., is doubtless a valid species, but the names 



alpicola and aureus are both older than Pollonera's 

 designation. The figures of alpicola given by Ferussac 

 (pi. 8 a. f. 2-3) look like A. subfuscus, and since there are 

 several different species of similar appearance, it may be 

 impossible to decide what Kerussac's slug really is. It 

 might even be specifically identical with my A. occidentalism 

 which is certainly not alpinus}* 



391. A. intermedins. It is doubtful which name should be 



preferred for this. I do not know A. flaws, Nilss., as 

 distinguished by Pollonera, but if it has good structural 

 characters, it seems almost hopeless to identify the names 

 of older authors with it or intermedins. The oldest flavus 

 is that of Midler, 1774, an inch and a half long, yellow, 

 spotless, white beneath, found in Denmark and Norway. 

 It has black tentacles. This is not L. flavus, Linn., of 

 course, and all the slugs at that time being in Limax, 

 Mallei's name was altered to aureus, on account of pre- 

 occupation, in 1778. 



Now doubtless flavus. Mull., is an Arion, and if it is 

 flavus sens Poll., or intermedium, the name must be used. 

 Probably it will never be identified with certainty, and so 

 it remains on the lists as a doubtful, — chiefly of importance 

 because it prevents us from admitting a later flavus into 

 the nomenclature. Consequently, although I leave A. flavus, 

 Nilss., on the list, following Pollonera, it would be more 

 correct to write : — 



380. A. campestris, Mab. 



flavus, Nilss., Poll. (? Mull.) 

 The name campestris applies strictly to an orange form, and 

 the yellow form might be distinguished as a variety. 



1 " F&rusac's figure, if not subfuscus is very closely allied to it, whereas the A. occidentalis, 

 Ckll., belongs to the hortensis group. In my opinion, it \*A. hortensis. — W '. E. C 



