1915- ^O. 12. THE STROPHOMEMDAE OF THE KRISTIAXL\ REGION. 6r 



Observations. The sinuosity of the outline at front as shown 

 in Verneuil's illustration (1. c.) does not exist in the best preserved Nor- 

 wegian specimen, but all other characters correspond so exacth" that 

 there is no doubt about the identity. This little species is undoubtedly 

 nearly related to 5. antiquata Sow. The general form, with sinus and 

 fold well developed, and the typical surface marking with the small 

 irregular depressions, strongly reminds one of the larger specimens men- 

 tioned above. 



Occurrence. 8 b— d. Ringerike; Bundetjord; Holmestrand; 

 Skien — Lancesund district 



Strophomena Scoßeldi Winchell and Schuchert. (?) 

 (PI. XIII, fig. 3.1 



1892. Strophomena scofielcii \V. and S. American Geologist IX p. 286. 



1892. Streptorhynchus stibsulcatutn Sardeson Bull, Mtaaesota Acad. Xat. Sei. III. p. 



335, pi. 4, fig. 39 



1893. Strophomena scofieUi W. a. S. Minnesota Geo!. 5ur%-ey III, p. 389. pi. XXXI, fijs. 



18 — 21. 



As onW a single incomplete dorsal valve is at hand, no certain iden- 

 tication can be made. It is beyond doubt, however, it\zt this form must 

 be very nearly related to the North American Trenton form cited. The 

 specimen present is probably somewhat flattened out by pressure, but 

 still an indication of a dorsal fold is preserved. 



Another North American form that ver}' much resembles the Norwe- 

 gian specimen is Strophomena sulcata Verxeuil from the Richmond, which 

 as explained b}' Winchell and Schuchert differs from S. Scofieldi b}' a 

 more profound fold and sinus, somewhat greater size, and less numerous 

 radiating striae, the two forms being, however, exceedingly nearly related. 



Occurrence 4 b (probably highest part of that horizon, correspon- 

 ding to the upper part of the Coelosphaeridium zone of the Mjosen 

 district), Eastern shore of the Randsfjord, South of Reikenvik, Hadeland. 



Strophomena sp. 

 (PI. XIII, fig. 4 ) 



A fragmentary free specimen, and a dorsal valve in rock are all that 

 are present of this form, the material being too poor to convey a detailed 

 knowledge of the form. In general appearance it comes near to the vounger 

 form described below, the outline being, however, somewhat broader. 



