60 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. IO3 



Signal ATountain formation; (Iocs. I2i, j) 2 miles southwest of 

 .Signal Mountain, Wichita Mountains, Oklahoma. 

 Holotypc. — U.S.N.M. No. 108737; paratypes Nos. io8738a-c. 



STENOPILUS ADUNCUS, new species 

 Plate 10, Figures 14-17 



A second species is chosen for description to show the elongate 

 form taken hy species of Stcnopilus. This development recalls the 

 Bymimia elongation of the Kingstonia stock, but in Sienopilus this 

 attends obesity and elimination of all furrows. As a result a snujoth 

 trilobite is developed, so convex that the glabella overhangs the 

 posterior margin. This high convexity is reduced forward, but the 

 curvature is not eliminated in any portion of the test. 



6^. adiiuciis is longer than wide and has its greatest convexity at 

 the rear. Otherwise it is practically featureless. 



Signal Mountain formation ; (loc. 12L) Pickens Ranch, Arbuckle 

 Mountains, Oklahoma. 



Hololypc. — U.S.N.M. No. 108739a; paratype, No. 108739b. 



BLOUNTIA Walcott, 1916 



BLOUNTIA PLANA, new species 



Plate 14, Figures 12-14 



Only pygidia have been assigned to the species. While the long 

 axis is defined, and the usual interrupted axial furrows are visible, 

 it does not stand above the pleural lobes. The chief characteristic of 

 the species is found in the flatness of the pygidium. When viewed 

 from the rear, the pleural platforms, with the axis, form only a 

 slightly convex shield. The border is slightly concave, thereby in- 

 creasing the curvature near the lateral margins. 



Sullivan formation; (loc. 64c) Glacier Lake Canyon Valley, 48 

 miles northwest of Lake Louise, Alberta. 



Holotypc. — U.S.N.M. No. 108779a; paratype, No. 108799b. 



BLOUNTIA KINDLEI, new species 

 Plate 14, Figures 27-31 



Two small pygidia and a portion of the cranidium are figured. A 

 somewhat broken pygidia is included to show appearance of the test ; 

 one much larger pygidium has not been figured. This species, which 

 is named in honor of the collector. Dr. Cecil Kindle, is typical of the 

 genus in every respect. 



