THE NAUTILUS. 99 



sent out under this name, it may be well to say that this shell is 

 somewhat triangular with rounded margins, nearly as large and 

 solid as the average P. variabile, horn colored shading to yellow at 

 the borders, some specimens with dark blotches or stripes near the 

 basal margin. The California types were described as having 

 " valves shallow in the cavity," but the northern shells are more full 

 and rounded. 



P. randolphii n. sp. Shell rounded oval, moderately inflated; 

 anterior end elongated and perfectly rounded, no angle indicating 

 the junction of the anterior and basal margins; posterior margin 

 sloping abruptly from the very short hinge margin ; beaks decidedly 

 posterior, fairly prominent ; surface very finely and evenly striated, 

 polished, of a most peculiar greenish-yellow color, different from 

 other Pisidia, but much like some Corbiculas. This of itself makes 

 it easy to separate from P. abilltum and P. variabile, associated spe- 

 cies. Long. 0'18 inch ; lat. 0'14 inch ; diam. O10 inch. Found at 

 Seattle. Dr. J. G. Cooper says the shell most nearly resembling 

 this is P. harfordianum Pr., a species practically unknown to collect- 

 ors, and of which he has only a young specimen. 



P. - ? n. sp. A rotund, orbiculate, dull yellow Pisidium, 



with prominent beaks and projecting scutellum, was collected by 

 Mr. Hemphill in Patten Lake, Whatcom County. Dr. Sterki con- 

 siders it identical with a species apparently common in the region 

 of the Great Lakes, to which he has applied the name P. scutellatum 

 (in letters). A deep water form is supposed to be P. abyssonim Stimp., 

 but as Dr. Stimpson's manuscript was destroyed by fire, and his 

 types mixed, this can never be certainly known. Figures and more 

 minute descriptions of this -and P. randolphii may be expected in 

 Dr. Sterki's coming monograph. Additional specimens are urgently 

 desired of this and other species of the Pacific Slope, which are, at 

 present, deplorably scarce. 



I believe it is safe to say that P.insigne Gabb., P. harfordianum 

 Prime and P. angelicnm Rowell are unknown, except from the 

 original lots. P. occidentals Newcomb seems to be only a form of 

 P. abditum Hald. Additional specimens may confirm that view or 

 prove the contrary. The most experienced collectors disagree re- 

 garding the identity of the Sphseria. This tangle need not long 

 remain if sufficient material can pass under the eye of a competent 

 conchologist. Pacific coast collectors have generally given their 

 attention to marine and land shells, and it would seem that a field 

 for discovery is open among the freshwater species. 



