350 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 64 



Formation and locality. — Middle Cambrian: (55c) Spence shale 

 member of the Ute formation; about 50 feet (15.2 m.) above the 

 Brigham qu^tzite, and 2,755 ^^^t (839.7 ^'^•) below the Upper Cam- 

 brian, in a ravine running up into Danish Flat from Mill Canyon, 

 about 6 miles (9.6 km.) west-southwest of Liberty and 15 miles 

 (24.2 km.) west of Montpelier, Bear Lake County, Idaho. 



BATHYURISCUS (POLIELLA) BALUS, new species 



Plate 49, figs. I, la-g 



This is one of the species occurring in an argillaceous shale that 

 has been compressed and distorted more or less by the movement in 

 the sediment. Fortunately its remains are abundant and afford data 

 from which a very fair conception of the species may be obtained. 



Bathyuriscus (Poliella) baltis has the elongate eye lobe and small 

 pygidium characteristic of B. (Poliella) powersi (pi. 46, fig. i) and 

 B. {Poliella) primus (pi. 46, figs. 6, 6a-b). Specimens occur with 

 nine and others with 10 thoracic segments. The sharp spines on the 

 occipital ring of the cranidium and the median lobe of all of the 

 thoracic segments are similar to those of B. (Poliella) powersi. Sur- 

 face not preserved. 



The larger specimens range from 25 to 30 mm. in length. 



This species is associated with : 



Lingulella sp. undt. (486) 

 Acrothele yorkensis Walcott (48d) 

 Acrotreta (48d) 

 Cystid plates (48) 

 Agnostus (48, 48d) 

 Ptychoparia (48) 



Formation and locality. — Middle ? Cambrian : York ? formation ; 

 (48) cellar diggings, corner of Penn and North Streets ; and (486) 

 argillaceous shales in railroad cut alongside of Gas House, both in 

 City of York, York County, Pennsylvania. 



BATHYURISCUS (POLIELLA) CARANUS, new species 



Plate 46, fig. 8 

 This fine little species, 10 mm. in length, is represented in the 

 collections by one specimen of the dorsal shield exclusive of the free 

 cheeks. It has seven thoracic segments, the pleural furrows of which 

 are broad near the axial lobe and narrowing gradually toward the 

 abrupt outer termination of the segment. Surface slightly roughened 

 by very fine, irregular inosculating edges. 



