100 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. IO3 



scattered granules. Beneath the anterior furrow a somewhat irregular 

 row of granules is present. 



Dry Creek shale ; (loc. 153) north of Gallatin River, east of Logan, 

 Horseshoe Hills; (Iocs. 147a, 151, 152) Churn and Cottonwood 

 Canyons, Bridger Range ; Davis Creek, south of Livingston, Snowy 

 Range, Montana. 



Holotype. — U.S.N.M. No. 108823a; paraty pes, Nos. io8823b-g. 



TAENICEPHALUS HOLMESI, new species 

 Plate 19, Figures 24-27 



The glabella which tapers to a rounded front, has three pairs of 

 fairly deeply impressed furrows. The brim width exceeds more than 

 half the glabellar length. At the center the brim is divided about 

 equally between rim and preglabellar area, both of which have about 

 the same convexity. At the eye the fixigenes are almost exactly equal 

 to half the glabellar width. The small eyes are situated about the 

 midpoint of the cranidium. They are very strongly bowed in a longi- 

 tudinal direction, which, together with the distinctness of the palpebral 

 lobe, projects the eyes considerably above the remainder of the cranid- 

 ium. In cross section the glabella is moderately, and the fixigenes 

 greatly, curved. Although individual parts have high relief the longi- 

 tudinal curvature is not great and is rather evenly distributed. The 

 pygidium, typical in size and shape, has considerable convexity. 



The specific name is given in recognition of the geologic work done 

 by the collector, Dr. W. H. Holmes. 



Dry Creek shale; (loc. 66x) Gallatin Valley, northwestern Yellow- 

 stone National Park, Wyoming. 



Holotype and paratypes. — U.S.N.M. No. 9595. 



TAENICEPHALUS SPECIOSUS, new species 

 Plate 20, Figure 19 



This rather large species found in the northeastern part of the 

 Yellowstone National Park differs from T. holmesi in that all 

 furrows are shallower, and the brim is wider. Also, the glabella and 

 fixigenes are less highly arched in both directions. The surface is 

 smooth. 



Dry Creek shale; (loc. 62r) Abiathar Mountain, northeastern 

 Yellowstone National Park, Wyoming. 



Holotype. — U.S.N.M. No. 108831a; paratype. No. 108831b. 



