LYMN^EIDJE OF NORTH AMERICA. 449 



ANIMAL, JAW, RADULA and GENITALIA : Not examined. 



RANGE : Idaho west to Oregon. A species of the Columbia River 

 drainage (Columbian region) in the Transition life zone. 



RECORDS. 



IDAHO: Salmon River (Hemphill). 



OREGON: Willamette (Wahlamat) near its junction with the Columbia 

 River, Columbia Co. (Lea; Nuttall). 



GEOLOGICAL DISTRIBUTION : Unknown. 



ECOLOGY : Similar to that of apicina. 



REMARKS : Solida may be known by its somewhat oblique, acutely 

 conic and imperf orate shell, its wide and rather fiat inner lip, its very 

 solid shell and its somewhat patulous aperture. Students have gener- 

 ally misunderstood this race (and this is not strange, since the figures 

 and descriptions are poor and meager), confounding it particularly 

 with decollata. The Michigan references to decollata were founded 

 on apicina and the western references on the present race. The figures 

 of solida and apicina have been very unfortunate. Haldeman's are 

 fairly good but Binney's are very poor and one can scarcely believe that 

 the figure given by him and the photograph of the type in this mono- 

 graph (pi. XLVIII, fig. 2) are intended to illustrate the same speci- 

 men. Solida differs from apicina in its more elongated spire, closed 

 umbilical region, less tumid whorls, more oblique shape, patulous aper- 

 ture and less acute columellar plait. It does not seem to be common 

 and only one lot, besides the type, has been seen. 



Notwithstanding the fact that Lea described solida on an earlier 

 page than apicina, the writer has deemed it best to consider the earlier 

 name a race of the later species. 



Galba hinkleyi (Baker). Plate XLVII, figure 31-35. 



Lymnaa hinkleyi BAKER, Nautilus, XIX, p. 142, April, 1906. 

 fLimnea catascopium HALD., Mon. Lim., p. 8, pi. 14, fig. 4, 1842 

 SHELL : Varying from ovate to globose, very thin ; color of per- 

 iostracum light greenish-horn; surface dull to slightly shining, rough, 

 the growth lines uneven and raised at intervals to form fine ridges; 

 the surface is sometimes malleated and occasionally ornamented by five 

 or six heavy spiral ridges ; fine impressed spiral lines present and very 

 marked in some specimens; whorls 5, rounded, tumid in some speci- 

 mens, the last whorl globose; spire of variable length, but generally 

 shorter than the aperture, broadly conic ; sutures well impressed ; aper- 

 ture roundly ovate, not expanded, acutely narrowed at the posterior 

 angle ; outer lip thin with an internal longitudinal varix "; inner lip very 



