20 SMITHSONIAN MISCFXLANEOUS COLLECTIONS VOL. 97 



SCENELLOPSIS, n. gen. 



A peculiar form from China, referred with reservation to Sccnclla, 

 seems to be a gastropod. 



Sccncllopsis is a small limpetlike shell with somewhat eccentric 

 apex. Both growth and radiating lines are present but are preserved 

 in two different specimens. Muscular impression, evidently branch- 

 ing, produces folds on the outer surface. 



Genotype. — ScencUa clotJio Walcott. 



Scenellopsis dilatata (Walcott) 



SccncUa ? dilatatus Walcott, Proc. U. S. Nat. Mus., vol. 30, p. 570, 1906; 

 Research in China, vol. 3. Carnegie Inst. Publ. 54, p. 87, pi. 5, figs. 2, 2a, 

 1913. 



Middle Cambrian, Changhia ; (loc. C70) southeast of Tungyii, 

 Shansi, China. 



Cotypes.—VS.^M. nos. 57767, 8. 



Scenellopsis clotho (Walcott) 



Sccnclla clotho Walcott, Proc. U. S. Nat. Mus., vol. 29, p. 12, 1905 ; Research 

 in China, vol. 3, Carnegie Inst. Publ. 54, p. 86, pi. 5, figs. 3, 3a, 1913. 



Middle Cambrian, Changhia; (loc. C18) East of Changhia, Shan- 

 tung, China. 



Holofype. — U.S.N.M. no. 57769. 



Scenellopsis saitoi, n. sp. 

 Sccnclla clotho Saito (not Walcott), Journ. Faculty Sci. Imp. Univ. Tokyo, 

 sec. 2, vol. 4, pt. 3. P- 359, ph 3, figs. 18, 19, 1936. 



This species resembles S. clotho, but, as pointed out by Saito, the 

 apex is not as high and the apertural margin is less upturned. Saito's 

 figures show that the marginal outline is also much more flattened at 

 the broad end. 



Lower Cambrian, Misaki ; near Chungwa, northern Chosen. 



Holotype. — Geol. Inst. Imp. Univ. Tokyo. 



. HYOLITHES Eichwald, 1840 



Eichwald established Hyolithes on H. acutus from Ordovician strata 

 of Estonia. The genus seems to be valid for other species extend- 

 ing from the Lower Cambrian into the Devonian. In the earlier 

 years Hyolithes was confused with various cephalopod genera, par- 

 ticularly Orthoceras but this confusion was cleared up long ago. Sev- 

 eral authors attempted classification of the family but no one has 

 completed the job. 



