190 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



Type (a coronate iudividual) : altitude 80, breadth 7, altitude of 

 body-whorl 6 mm. Co-type (a peripherally cnrinate individual): 

 altitude 7, breadth 6"3 ram. Co-type (a I'oiinded individual) : altitude 

 8*7, breadth 7 mm. 



Pliocene : Kettlemau Lake beds, California. 



Hills borderinjj Tulare Yalley on west, California; Martin and 

 Dudley's oil-well, south-east quarter of section 32, township 26 

 south, range 21 east, Lost Hills (types) (W. Williams); east of 

 Dudley-Leraoor road, south-west quarter of section 17, township 23 

 south, range 19 east, east border of Kettlenian Hills (Ferguson); 

 opposite Tulare Lake, west border of Kettleman Hills (W. L. Watts), 

 fide Watts; well at depth of 1,058 feet, Lambertson's ranch near 

 "Tulare Lake (W. L. Watts), /^^ Watts. 



P. Williamsi is tlie largest and most compact Pjirgidopsis yet 

 described, though Yatesiana approaches it somewhat. The prevalent 

 type in the Kettlemans appears to be the rounded form, and upon 

 this it seems almost certain that Cooper founded his record of Amnicola 

 turhiniformis [Fluminicola semvialis). This is the onlv species in these 

 deposits which resembles a Fluminicola particularly, but, owing to 

 the destruction in the San Francisco fire of the material on M'hich 

 Cooper based his report, which was among the California Academy 

 collections, there has been no opportunity of verifying such a 

 supposition. In the Lost Hills no exposures of these lake beds are 

 known, but through the courtesy of Mr. W.Williams, chief geologist 

 of the Associated Oil Company, the writer is indebted for some 

 interesting material derived from an oil-well at a considerable depth. 

 In this set, rounded, peripherally carinate, and coronate individuals 

 are present, the latter prevailing. From one of these the type has 

 been selected. 



Genus CiNCiNNATiA, Pilsbry. 



Paludina (sp.), Anthony, 1840 {P. Cincinnatie7isis, Anth.); Amnicola 

 (sp.), Anthony, 1843 (P. Cinchinatiensis, Anth.); Cincinnatia, 

 Pilsbry, 1891 {P. Cincinnatiensis, Anth.). 



Type, Paludina Cincinnatiensis^ Anthony. 



Shell of moderate size, averaging 5 mm. in altitude, elevated 

 conic-globose, epidermis horn-coloured, whorls strongly inflated and 

 umbilicate, sutures deep, spire elevated and sub-pupiform, apex bluntly 

 obtuse, aperture sub-circular, peritreme complete; habitat lakes and 

 sluggish streams. 



The genus contains, so far as known, two species, C. Cincinnatiensis. 

 which should not be confused with ' Cyclostoma'' Cincinnatiensis, \^q;\, 

 a P omaliopsis, and C. Binncyayia, nora. nov.' 



' I'aludina obtusa, Lea, 1841, not of Trosehel, 1837. This has passed in the 

 hterature as Paludina emarginata, Kiister. Whether or not Kiister had 

 this shell before him is of no consequence ; he identifies his species 

 with Lymncpus emarginatus, Say ; hence the name is entirely inadmissible 

 in this connexion. Lea's name is a homonym, therefore C. Bmneyaiia 

 may be substituted. 



