222 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 64 



Thorax. 



Length 3-5 



Width of first segment 8 



Width of axial lobe 3 



Pygidium. 



Length 5 



Width of axial lobe 2.5 



Observations. — The associated fauna at localities 4V and 5J 

 includes : 



Micromitra (Iphidclla) pannula (White). 



Obolus (IVestonia) ella (Hall and Whitfield). 



Acrothele colleni Walcott. 



Acrothele panderi Walcott. 



Wimanella simplex- Walcott. 



Ptychoparia sp. 



Olenopsis americanus Walcott. 



Albert ella helena Walcott. 



Bathyuriscus ? sp. 



Vanuxemella contracta Walcott. 



This fauna is of the same type as that found with Vanuxemella 

 nortia in Canada (see p. 223). 



Formation and locality. — Lower Cambrian: (4V) About 200 feet 

 (61 m.) above the unconformable base of the Cambrian and 75 feet 

 (22.9 m.) above the top of the quartzitic sandstones, in a shale which 

 corresponds in stratigraphic position to shale No. 6 of the Dearborn 

 River section, Gordon Creek, 6 miles (9.6 km.) from South Fork of 

 Flathead River, Ovando quadrangle (U. S. G. S.) ; and (5J) above 

 the quartzitic sandstones, in a shale corresponding to the same posi- 

 tion, about 6 miles (9.6 km.) west-northwest of Scapegoat Mountain, 

 on the Continental Divide between Bar Creek and the headwaters of 

 the south fork of North Fork of Sun River, Coopers Lake quad- 

 rangle (U. S. G. S.), both in Powell County, Montana. 



VANUXEMELLA NORTIA, new species 



Plate 36, fig. 5 



This species dififers from J^annxemella contracta in having a 

 greater expansion of the glabella towards the frontal margin ; longer 

 palpebral lobes ; five instead of four thoracic segments, and smaller 

 posterior spines on the pygidium. 



The fauna associated with this species includes at locality 35c 

 the following : 



