214 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 64 



mens occur in both argillaceous shale and shaly dark bluish-grey 

 limestone. 



Upper Cambrian: (i6a, 89) Conasaug'a formation; shaly lime- 

 stone interbedded in argillaceous shales, Murphrees Valley, Blount 

 County; and (139a) near Chepultepec, Jefiferson County, both in 

 Alabama. 



CREPICEPHALUS TEXANUS DANACE, new variety 

 Plate 29, figs. 3, 3a 



This variety is represented by a single cranidium. It differs from 

 C. texanus by having the glabella less convex, a trifle more elongate 

 proportionally, and more transverse at the anterior end ; and the 

 frontal border is more rounded. Surface granulated as in C. 

 texanus. 



Formation and locality. — Upper Cambrian: (79d) Eau Claire 

 formation; upper beds of sandstone on Mount Washington, near 

 Eau Claire, Eau Claire County, Wisconsin. 



CREPICEPHALUS TEXANUS ELONGATUS, new variety 



Plate 29, figs. 4, 4a 



Of this species the cranidium only is known. It is characterized 

 by a proportionally longer glabella and narrower fixed cheeks, with 

 a broad flattened frontal border. The transverse frontal furrow is 

 also less deeply impressed than in typical specimens of C. texanus. 



The surface of the test in both the Wisconsin and Montana speci- 

 mens has coarse tubercles scattered irregularly on the glabella, fixed 

 cheeks, and frontal limb. 



Formation and locality. — Upper Cambrian: (796) Eau Claire 

 formation; i mile (1.6 km.) north of Eleva, Trempealeau County, 

 Wisconsin. 



Upper Cambrian: (151!) Gallatin limestone; north side of Smith 

 River; 1.5 miles (2.4 km.) below mouth of Fourmile Creek, and 

 6 miles (9.6 km.) northeast of White Sulphur Springs, Meagher 

 County, Montana. 



CREPICEPHALUS THOOSA, new species 



Plate 31, figs. I, la-k 



This species is based on cranidia and associated free cheeks and 



pygidia. It is of the C. texanus type, and differs from it in its more 



elongate, conical glabella, short frontal limb, and more thickly-set 



surface granules that occur on the cranidium, free cheeks, thoracic 



