NO. 3 CAMBRIAN TKILOBITES 20$ 



Formation and locality. — Lower Cambrian: (30J Limestone 8 

 miles (12.8 km. j north of Bennetts Spring, on the west slope of the 

 Highland Range; (aia) limestones of Pioche formation, just above 

 the quartzitc on cast sirlc of anticline, near l^ioche, both in Lincoln 

 County, Nevada. 



CREPICEPHALUS CAMIRO, new species 

 Plate 32, figs. 2, 2a 



This IS the Appalachian representative of C. iowensis. It differs 

 in its small glabella and broad frontal limb of the cranidium, and the 

 associated pygidium has about six faintly defined rings and a terminal 

 section on the axial lobe. The outline of the posterolateral borders 

 of the pygidium also differs materially by sloping inward, and the 

 two spines are shorter and nearer together proportionally with regard 

 to the size of the pygidium. 



Surface of test minutely pitted or apj^arently punctate under strong 

 lens, but smooth to the unaided eye. 



Formation and locality. — Upper Cambrian : (120) Maryville lime- 

 stone; north of Bays Mountain, on Beaver Creek, Sevier County, 

 18 miles (28.8 km.) east-northeast of Knoxville; and (107) Bull 

 Run Ridge, northwest of Copper Ridge, 11 miles (17.6 km.; north- 

 west of Knoxville, both in Tennessee. 



CREPICEPHALUS COMUS, new species 

 Plate 31, figs. 3, 2>a 



This species is represented by cranidia and associated pygidia. 

 The glabella is tumid as in C. tumidus, but the frontal limb is little 

 more than a narrow convex extension of the convex fixed cheeks 

 grading into the broad frontal groove which lies within the very 

 prominent, rounded frontal border. The three pits in the frontal 

 furrow are nearly round, and large for the size of the cranidium. 



Surface finely granulated and test apparently punctate. 



The largest cranidium in the collection has a length of 17 mm. 



The associated pygidia (fig. 3a) are much like those of C. thoosa 

 (figs. i/-fe). 



Formation and locality. — Upper Cambrian: (120) Maryville lime- 

 stone ; north of Bays Mountain, on Beaver Creek, Sevier County, 

 18 miles (28.8 km.) east-northeast of Knoxville; (107) Bull Run 

 Ridge, northwest of Copper Ridge, 11 miles (17.6 km.) northwest 

 of Knoxville; and (119) beneath Nolichucky shale on Cub Creek, 

 1.5 miles (2.4 km.) southeast of Morristown, Hamblen County, all 

 in Tennessee. 



