NO. 24 PTARMIGANIA STRATA RESSER _ 49 



KOOTENIA MENDOSA, n. sp. 



Plate 9, figs. 14-18 



This is a fairly common species, being represented by several 

 cranidia and pygidia, none of which is very well preserved. As shown 

 by the illustrations it is associated with Wimanella maladcnsis and 

 with Clavaspidella wasatchensis. 



The cranidium is characterized by a large prominent glabella which 

 extends well forward beyond the anterior angles. It tapers somewhat 

 forward. Pits at the anterior angles of the dorsal furrow strongly 

 restrict the glabella at that point. Viewed from the front the cranidium 

 'is very convex with the glabella sharply curved. In that view the 

 constriction in the forward end of the glabella is particularly notice- 

 able. The pygidium is peculiar in several respects. The axis is long 

 and of normal width, with the usual segments. The pleural lobes are 

 well fused, although the pleural grooves are still visible. The border 

 is of normal width. The outstanding peculiarity is the reduction of 

 the marginal spines to short spines on the first and second segments 

 and back of that to a slight waviness in the margin, becoming a 

 smooth even outline in the rear. 



Locality 20x. 



Holotypc and paratypes. — U.S.N.M. Nos. o,8538a-c. 



KOOTENIA GERMANA, n. sp. 



Plate g, figs. 19-24 



This is a small species associated with K. mcndosa. The glabella is 

 of normal size and composition, being rather highly arched in both 

 directions. The pygidium has six small, tapering marginal spines. 



Locality 20x. 



Holotypc and paratype. — U.S.N.M. Nos. 98539^1. 



KOOTENIA ACICULARIS, n. sp. 



Plate io, figs. 24-26 



One pygidium among the many Kootenia species at Two Mile 

 Canyon has sharp spines. A very small cranidium, which also does 

 not seem to belong with any other species is tentatively assigned to 

 the species. The pygidium is characterized by the usual long cylin- 

 drical axis. Fusion has been nearly sufficient to eliminate the pleural 

 grooves. A distinctive feature of the species is the extension of the 

 pleural furrows across the border. There are six pairs of very slender 

 marginal spines. The surface is smooth. 



