NO. 24 PTARMIGANIA STRATA RESSER 57 



KOCHIELLA MANSFIELDI, n. sp. 



Plate 11, figs. 10-14 



This species is abundant in the small amount of material collected 

 from this locality. It is associated with Dolichometopsis and Poulsenia, 

 as well as other genera. 



The glabella is little more than half the length of the cranidium 

 and tapers considerably to a slightly rounded front. The dorsal 

 furrow is definitely defined on the sides but becomes rather shallow 

 in front of the glabella. Three pairs of shallow glabellar furrows 

 may be noted. The fixigenes at the anterior end of the eye are nearly 

 as wide as the glabella at that point, and they expand from the rear 

 end of the eye forward owing both to the contraction of the glabella 

 and to the slight divergence of the anterior facial suture. The eyes 

 are of moderate size and situated rather far to the rear. Eye line 

 prominent. Brim wide, nearly straight in front. On the whole it is 

 concave, and when the doublure is impressed to show on the upper 

 surface a wide brim is indicated. The associated pygidium is nearly 

 quadrangular in outline with rounded anterior angles and slightly 

 contracted lateral margins. The anterior half of the first segment 

 forms a raised rim extending from the axis around the circular 

 anterior angles and then backward into spines, which possibly are 

 long. The axis is broad and has three axial rings, besides the terminal 

 segment. It is only gently arched above the pleural lobes. The pleural 

 lobes are nearly flat but slope down to the margin, and on them three 

 pleura are delimited by the pleural furrows. Surface of cranidium 

 covered by scattered large granules, overlying a small crowded set. 

 In the pygidium only the small granulations are present, but irregular 

 lines occur on the outer edges. 



Locality 19s. 



Holotype and paratypes.—'U.S.NM. Nos. 98557a-d. 



KOCHASPIS Resser, 1935 

 KOCHASPIS MALADENSIS, n. sp. 

 Plate 13, figs. 9-12 

 Three pygidia, but no cranidium, were found at this locality. These 

 pygidia constitute a typically developed species of Kochaspis. It is 

 possible that the cranidium is confused with the abundantly repre- 

 sented Poulsenia granulosa. 



The pygidium is characterized by a prominent axis, which stands 

 entirely above the pleural platforms. The axis is nearly semicircular 

 in cross section and occupies nearly the full length of the pygidium. 



