40 SMITIISOMAN MISCIil.I.ANEOUS COLLECTION'S VOL. IO3 



ILLAENURUS ELONGATUS (Walcott) 



PlaVe (), FicuRES 18, 19 



']'simi>iia clonijata Walcott, Sniitlisoniaii Misc. Coll., vol. 64, No. 3, p. 228, 

 pi. 36, figs. 10, loa, 1916. 



The cranidium on which this species is based is not average for 

 Illaciiurus. It is long and narrow, with Httle curvature in cross section 

 l)ut with somewhat more in longitudinal section. No dorsal furrow 

 or rim seems to be differentiated. The anterior angles are rounded 

 more than average for the genus. The eyes are about normal size, 

 situated slightly forward of the glabellar midpoint. 



McKay group; (loc. 23Z) 2 miles west of Donald, Dogtooth 

 Mountains, British Columbia. 



Holotyl^c.—U. S.N. M. No. 61736. 



PLATYCOLPUS Raymond, 19 13 

 PLATYCOLPUS QUINNENSIS, new species 



Plate 6, Figures 16, 17 



The small collection from this locality has yielded a good cranidium 

 of Platyculpns, which is described because of its significance in the 

 fauna. It is normal in all essential characters of the genus. A wide 

 glabella, faintly indicated by a shallow dorsal furrow, extends a little 

 in front of the eyes. The rim is wide and heavily striated. Anterior 

 to tlie eyes the facial suture diverges, forming large anterior angles. 

 The eyes are of moderate size, situated well back on the head. A 

 shallow occipital furrow delimits a wide flat occipital ring. 



Mendha limestone; (loc. 7J) Quinn Canyon Range, Nevada. 



Holotypc— {J.S.N. M. No. 108692. 



PLATYCOLPUS OKLAHOMENSIS, new species 

 Plate 6, Fig r res 20-25 



This species is recognized at several localities. As usual only frag- 

 ments of the cranidium are preserved, a condition characterizing most 

 species thus far recognized in the genus. The portion of the glabella 

 available shows that it is wide, and rather evenly but not highly arched 

 in both directions. It has the usual wide brim, although it lacks the 

 usual striations. 



The pygidium is normal in every respect. Exfoliated specimens 

 show a well-se])arated axis. On the outer surface it is marked simply 



