44 SMITIISOXIAN MISCELI.ANKOUS COLLECTION'S VOL. I03 



The pygidium is short and wide, with a large axis, which seems to 

 be segmented in all species. Some species have well-developed pleural 

 furrows, and a few show a border. 



ARAPAHOIA TYPA Miller 



Plate 7, Figures 37, 38 

 Arapahoia typa Millek, Journ. Pal., vol. 10, No. i, p. 25, pi. 8, fig. 6, 1936. 



The figured specimens from the Beartooth Mountains are identified 

 with the type species. However, without the holotype at hand for 

 comparison, this identification is not without question. 



Maurice formation ; Butte north of Little Rocky Creek, Beartooth 

 ^^Tountains, Wyoming. 



Holotype. — Columbia Univ. No. 12612; plesiotypes, U.S.N.M. Xo. 

 108708.' 



ARAPAHOIA STANTONI, new species 



Plate 7, Figures 2-4 



This species is similar to A. spatulata Miller in that the glabella is 

 not separated by relief from the fixigenes. The very shallow dorsal 

 furrow can be seen very clearly in cross light. The keel shows in 

 about the same degree as the glabella. Exclusive of the neck spine, 

 the holotype canidium, measured immediately in front of the eyes, is 

 13.7 mm. long and 8.8 mm. wide. The anterior margin of the brim 

 is slightly angulated. Few specimens retain the slender neck spine. 

 The associated pygidium has two pleural furrows clearly defined. 



Pilgrim formation; (loc. 26b) Mill Creek, Little Rocky Mountains, 

 Montana. 



Holotype. — U.S.N.M. No. 108699a; paratype, No. 108699b. 



ARAPAHOIA REESIDEI, new species 



Plate 7, Figures 5-9 



This species is represented by many specimens, but only a few can 

 be cleaned reasonably well. A. reesidci, named for the collector, Dr. 

 John B. Reeside, Jr., is nearly f^at in cross section but has more con- 

 vexity longitudinally. The brim is turned down rather sharply at the 

 margin. The dorsal furrow is expressed by shallow furrows on the 

 sides as far forward as the eyes; beyond that point there is only a 

 laiut indication of it. The eyes are in an elevated position. The 

 anterior facial suture diverges slightly. 



{ 



