WEST COAST PULMONATA. 17 



is also the prevailing color, like that of many dead forest- 

 tree leaves, and they are often blotched irregularly with 

 black, like leaves mouldy or decayed. The small species 

 and sub-species, A. niger, andersoni and hemphilU, are either 

 black, or pale with dark specks irregularly scattered on or 

 between the granulations, while the furrows separating these 

 are of the same light color. 



In Proplujsaon andersoni and hemphilU, the furrows are 

 darker than the tubercles, giving the " foliated" appear- 

 ance ascribed by Dr. Gould to an Oregon " Arion " (which 

 was probably of this more recent genus). 



A black variety of the former was also found by W. 0. 

 Emerson on the Santa Cruz Mountains among burnt logs, 

 where its color might have also been a protective variation. 



My reason for making No^. 7 and 8 only sub-species of 

 No. 6 {A. niger), besides the local limitations before men- 

 tioned, are that they do not seem to differ from that species 

 more than the forms of L. campestris called montanus and 

 occidentcdis differ from that species, and Mr. Binney now 

 admits that they intergrade with it. 



I am inclined to think that all the Limacoids except Limax 

 are biennial, taking most of two years for their growth, and 

 then dying, but some may live longer, especially those 

 hatched late in the season. 



Mr. Binney considers Prophysaon andersoni as " probably 

 a distinct species," founding this opinion on the genital 

 organs, bat the differences in form noted are such as are 

 likely to vary with season, and to change after oviposition. 

 In either case, the specific name is prior to that of P. liemp- 

 hilli, although T described it as an ''Avion''' before the 

 later genus was separated, noticing its resemblance to A. 

 foliolatus Gould. 



Vitrinoid. 



The distinctions separating this group from the Helicoid 

 may be broadly stated as the absence of thickened expanded 



2d Ser., Vol. I. 



2 



