Raymond : Gastropoda of the Chazy Formation. 173 



Genus Scenella Billings. 



Scenella montrealensis (Billings). 



(Plate XLVI, figures 9, 10; Plate LV, figure i.) 



Metoptoma montreale?tsis Billings, 1865, Paleozoic Fossils of Canada, 



Vol. I, p. 394, fig. 371. 

 Scenella montrealensis Ulrich and Scofield, 1897, Paleontology of 



Minnesota, Vol. Ill, part II, p. 838. 



Billings' original description is as follows : " Acutely conical ; apex 

 a little in advance of the center ; base obtusely elliptical, the antero- 

 posterior diameter a little the longest. On a side view the outline is 

 gently convex from the apex to the posterior, and concave to the an- 

 terior margin. Surface, when perfect, with fine vertical striae running 

 from the apex to the margin, and with both fine engirdling striae and 

 obscure undulations of growth parallel to the base. In most specimens 

 the fine striae are not perceptible." 



The specimens from Chazy, New York, the locality in which this 

 species has been found by the writer 1 very rarely show radiating striae, 

 although the shell is preserved. On these specimens, especially near 

 the aperture, the " obscure undulations of growth ' ' are very prominent. 

 A specimen in the United States National Museum which is here fig- 

 ured (Plate LV, figure 1) through the courtesy of Dr. Bassler, shows 

 the vertical striae, which are often interrupted by the concentric undu- 

 lations and give the shell much the appearance of a worn coral. This 

 specimen is from Isle La Motte, Vermont, where this fossil is com- 

 mon in association with Raphistoma stamineum, Bucania sulcatina, 

 Pliomerops canadensis, and other characteristic fossils. 



Scenella pretensa Raymond. 

 (Plate XLVI, figures n-13.) 



Scenella pretensa Raymond, 1905, American Journal of Science, Series 



4, Vol. XX, p. 375. 



A rare species found with the last differs from it principally in its 

 narrowly elliptical aperture and generally compressed form. 



1 The specimens from the Crown Point section which were identified as Metoptoma 

 montrealensis, did not belong to that species but to Archinacella ? propria. Bulletin 

 American Paleontology, No. 14, 1902. 



