COCKERELL : NOTES ON AGRIOLIMAX MONTANUS. 359 



spirit specimens. It appears, therefore, that IngersoH's slugs 

 were both described from specimens preserved in alcohol ; 

 castaneus being a young example and monta7iiis an older one, 

 the bluish-grey color being due for the most part to an exudation 

 of slime, such as is often witnessed in specimens which have 

 been put into alcohol. 



The tentacles of castaneus were doubtless very dark brown 

 (as I have myself observed in examples collected in the Blue 

 River Valley), and the very pale sole of some examples would 

 probably appear white in an alcholic specimen. 



There is, then, but one species of slug at present known in 

 Colorado, and this is Agriolimax campestris montanus Ing. It 

 varies, however, in colour, and I have separated three forms : — 



A. typicus. — Rather pale brown, foot-sole pale. 



B. intermedius. — Dark brown, foot-sole grey. 

 c. tristis. — Very dark brown or brown-black. 



I have endeavoured to trace this variation to some definite 

 cause, but although it can be said that tristis and intermedius 

 belong to high, and typicus to middle elevations, this does not 

 always hold good. Like IcBvis this species is nearly always 

 found in damp places. 



My experience with the various forms of this slug has been 

 as follows, from which it will be seen that I obtained it in thir- 

 teen localities : — 



(i). Atlantic slope. 

 (a). Swift Creek, Custer Co., Aug., 1887, under Populus 

 tremuloides,on logs, &c.; altitude about 8,200 ft. — typicus. 

 (b). Nathrop, Chaffee Co., August, on under side of log ; 



altitude about 7,680 feet — typicus. 

 (c). E. Fork of Arkansas, R., Lake Co., August, near 



willows ; altitude about 10,200 feet — tristis. 

 (d). Saguache Creek, above Rock Cliff, Saguache Co., 

 October, found together under an old tree — typicus 

 and intermedius. 



