78 THE NAUTILUS. 



a. Jaw ribbed, P. fasciatum. 



b. Jaw only striate, ... P. humile. (Until more material 

 of humile is seen, it cannot be made sure that the jaw-character is a 



specific one.) 



My present opinion is that Pkenacarion must be merged in Pro- 

 physaon s. str. 



In order to further elucidate some of the forms of Prophysaon, I 

 give below some of my notes, made years ago, but not published at 

 the time. 



Prophysaon hemphilli W. G. Binney (as Phenacarion~). 



This must not be confounded with P. hemphilli B. and B., which 

 I consider specifically identical with andersoni. I know little more 

 about it than may be gathered from Mr. Biuney's account. Mr. 

 Binney sent me one from near the mouth of the Chehalis River, and 

 I noted at the time: looks like type foli.olatus in alcohol. Sole pale 

 yellowish white. Edge of foot dark, with darker transverse lines. 

 Body bluish-gray, tapering ; mantle more brownish. 



Prophysaon foliolatum (Arion foliolatus Old.). 



Comparing this with P. hemphilli B. & B., I noted : Sole white, 

 oblique transverse grooves visible. Transverse dark streaks on 

 edge of sole more strongly marked, alternating strong and weak 

 Body exactly the same color (in alcohol) as hemphilli B. & B. Pale 

 dorsal line very slightly indicated. Reticulations practically as in 

 hemphilli, but foliations more distinct. Mantle not so dark and 

 brownish-tinged ; bands represented by subcoalesced black marks ; 

 black spots scattered about. As I wrote in An. Mag. N. Hist., 1890, 

 " it is most difficult to separate P. foliolatum and Proph. hemphilli 

 (i. e. andersoni) specifically." An alcoholic example of hemphilli 

 differed from foliolatum as under 



Prophysaon hemphilli B. & B. 



Sole slightly yellowish, only wrinkled transversely. Marks on 

 edge of sole quite similar, but not so well marked. Body purplish 

 mouse-color, i. e., gray with a lilac tinge. Mantle dark, with indis- 

 tinct " smoke colored band." Body tapering. No mucus pore. A 

 pale dorsal line is barely indicated just behind mantle to half length 

 of back. Slug 42 mm. long. 



