Mr. T. D. A. CockerelFs Notes on Slugs. 329 



Ecuador being merely the result of an accidental importation, 

 while Pirainea has species in the most distant parts of the 

 globe, and is almost cosmopolitan in temperate regions, where 

 the climate is damp and fairly uniform. Dryness and ex- 

 tremes of temperature seem unfavourable to it, so that we get 

 no representatives in Eastern Europe, temperate Asia, or 

 Eastern North America. In considering the species of 

 Pirainea, it will be convenient to arrange them under the 

 various regions in which they occur. 



a. European Region. 

 Amalia g agates (Drap.). 



A very polymorphic species, not very variable in any parti- 

 cular locality, but differing very much in the different regions 

 which it inhabits. English specimens are smaller than those 

 from the Mediterranean Region, and not so dark, being also 

 much smoother and more pellucid. The forms found on the 

 borders of the Mediterranean are often very large, intensely 

 black, and quite rugose. Generally speaking, in warm 

 climates the species seems to become darker, more opaque, 

 and more rugose. If we compare an English example with 

 one from Sicily it is hard to believe that they are even closely 

 allied. 



Limax gagates, as figured by Draparnaud (Hist. Nat. Moll. 

 1805, pi. ix. figs. 1, 2), looks like the English form, but is 

 described as black, shiny, with the body striate-subrugose. 

 This must be considered the type. It is the var. typus of 

 Lessona and Pollonera, and is a phase of the species met with 

 in many localities where gagates is found. It differs from the 

 usual English race in being black and more rugose ; but it is 

 not so rugose as some of the Mediterranean forms, and is only 

 of moderate size. 



Ferussac's figures of L. gagates (Hist. Nat. Moll. pi. vi. 

 figs. 1, 2) resemble the English form more nearly as to colour 

 and agree in size ; but fig. 1 has the rugse rather too strong. 

 Moquin-Tandon's plate ii. fig. 1 is like the English race, 

 but the mantle has small spots j these spots are not mentioned 

 in the description. 



It thus appears that Amalia gagates in France, although 

 much like the English form of the species, tends to become 

 more rugose and darker, thus approaching the southern 

 varieties. But in the north of France at least the var. 

 plumbea is found not at all different from those in England. 



