286 
PROCEEDINGS OF THE NATIONAL MUSEVM. 
VOL. XXIV. 
Fig. 4.— Amnicola 
M I C R f I (' O C C U S 
(Pilsbry). 
AMNICOLA MICROCOCCUS Pilsbry. 
Shell minute, globose, with short conic spire and narrow umbil- 
icus. Whorls 3f , convex, especially below the sutures, the apex very 
obtuse. Surface smooth, light olive colored. Aperture 
ovate, about half the length of the entire shell, bluntly 
angulated above; the inner lip is either free from the 
preceding whorl or in contact only at the upper part. 
Alt. 1.5, diam. 1.3 mm. 
A smaller species than A. granum. Say, with oval 
instead of round aperture and shorter spire. 
Type from small spring in Oasis Valley, Nevada 
(U.S.N.M., No. 123622), by Dr. C. Hart Merriam, June, 
1891. Collected also in Death Valley by Nelson and Bailey, February 
4,1891 (U.S.N.M., No. 123904). 
Several examples of this interesting little shell were detected as 
above. 
FLUMINICOLA MERRIAMI Pilsbry' and Beecher. 
Shell small, globose turbinate, narrowly but distinctly and deeply 
umbilicated. Spire low conic, acute; whorls four, slightly shouldered 
below the sutures, the upper lateral portion rather flattened, periphery 
and base convex. Surface smooth, horn-colored. 
Aperture oblique, ovate, angled above, broadly 
rounded below; upper portion of the inner lip 
adherent to the body whorl, lower portion arcu- 
ate, without a callous thickening. 
Alt. 3, diam. 2^ mm. 
This species differs from F. fasca Haldeman in 
the much more distinct umbilicus, thin texture, 
and the nonthickened lip. 
Collected from a warm spring (temperature 97° 
F.) in Pahranagat Valley, Nevada, by Dr. C. Hart 
Merriam, May 25, 1891 (U.S.N.M., No. 123626). 
Dr. Merriam detected in the same spring numerous living examples 
of the long-sough t-f or Tryonla dathrata Stimpson, previously known 
only by dead or semifossil examples collected by Prof. William P. 
Blake in 1855 and General Carlton in 1861-62. It is quite evident 
that the term "Colorado desert," as used in connection with the 
Blake-Carlton shells, included a much larger part of the Great Basin 
than is now understood when the "Colorado desert" is mentioned. 
Attention is again called to the Hgure "139, Tryonla dathrata^'''' as 
given in Binne}^^ which does not represent Dr. Stimpson's shell; for 
iThe Nautilus, V, Apr., 1892, p. 143; also XII, Mar., 1899, p. 121 et seq. 
^Smithsonian Miscellaneous Collection, No. 144, p. 71, Sept., 1865. 
Fig. 5.— FLUMINICOLA Merri- 
AMi (Pilsbry and Beecher). 
