140 COLORADO FORMATION AND ITS INVERTEBRATE FAUNA, [hull. 106. 



The aperture is obliquely ovate in outline, slightly narrowed behind 

 and a little produced or sub-canaliculate in front. Outer lip thin and 

 sharp j inner lip somewhat reflexed and thickened below ; peritreine 

 not continuous, coluninella somewhat arcuate. 



Length of one of the types with the apex restored, about 13 mm ; great- 

 est diameter, about 5 m,n . Some fragments of the same species evidently 

 belong to shells with about double these dimensions. 



With the imperfect material with which the paleontologist must 

 usually deal, it is very difficult to assign such forms as this to the genus 

 to which it belongs. Its general form and the character of the orna- 

 mentation are duplicated in Oerithiuw,, Scalar ia 7 and Rissoa, or at least 

 in species that have been referred to those genera. The fact that in 

 our species the peritreme is not continuous prevents its reference to 

 either Scalaria or Eissoa. It seems to be very nearly related to some 

 of the Cretaceous species of Mesostoma figured by Holzapfel, 1 and I 

 have therefore placed it provisionally in that genus rather than in 

 Cerithium. No described species from the American Cretaceous known 

 to me is nearly related to this one, though Cerithium lallierianum var. 

 suciense Whiteaves, seems to belong to the same general type. 



Locality and position. — In the Pugnellus sandstone, at several locali- 

 ties in Huerfano park, and in the upper part of the Benton shales on 

 the Arkansas river above Pueblo, Colorado. 



PYRAMIDELLID^E. 

 Genus EULIMELLA Forbes. 



EtTLIMELLA? FTJNICULA Meek. 



PI. xxx, Fig. 9. 



Enlima funicula Meek, 1873, Ann. Rept. 17. S. Geol. Sur. Terr, for 1872, p. 506. 

 Eulimella ? funicula White, 1876, U. S. Geog. and Geol. Sur., West 100th Meridian, Vol. 



iv, p. 197, PI. 18, Fig. 6; 1879, Ann. Kept. U. S. Geol. Sur. Terr, for 1877, p. 316, PL 



9, Fig. 10a. 



Original description : 



" Shell subterete or elongate-conical; spire regularly tapering from 

 the middle of the body volution to the apex, or with very slightly con- 

 vex slopes; volutions about twelve, flattened; last turn not much 

 enlarged, subangular around the middle; suture merely linear; aper- 

 ture ovate or rlumibic-subovate; inner lip slightly thickened and re- 

 flected. Surface smooth. 



"Length, 0.65 inch; breadth, 0.20 inch; divergence of slopes of spire 

 about 19o. 



" This shell has much the appearance of a slender Nisso, but it cer- 

 tainly wants the umbilicus seen in that genus, its axis not being in the 

 slightest degree perforated. It is even like some recent species of Euli- 



Die Mollusken der Aachener Kreide, Palseontographica, Bd. 34, p. 129 et seq. 



