144 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 75 



DESCRIPTION OF PLATE 24 



PAGE 



Xenostegium taurus Walcott 128 



Fig. I. (Natural size.) Dorsal view of the pygidium and an oblique 

 view of the cranidium. Ui S. Nat. Mus., Cat. No. 70357- 

 2. (X2.) Dorsal view of the type cranidium. 

 Matrix, limestone. 



Ozarkian, Chushina formation. (Loc. 6iq) : Billings Butte 

 (Extinguisher), above Hunga Glacier, Robson Peak District, Brit- 

 ish Columbia, Canada. 



Xenostegium belemnurum (White) 125 



Fig. 3. (X2.) Cranidium with test badly eroded on same rock with 

 fig. 4, the original type. U. S. Nat. Mus., Cat. No. 70358. 

 4. (Natural size.) Dorsal view of White's original type specimen. 

 Hologenotype, U. S. Nat. Mus., Cat. No. 8562. 

 Matrix, limestone. 



Canadian ? (Loc. 671) : Queen Spring Hill, southeast of Schell- 

 bourne, Nevada. 



Xenostegium goniocercum, (Meek) 127 



Figs. 5, 6. (Natural size.) Dorsal views of the original type pygidia 

 of the species. U. S. Nat. Mus., Cat. No. 11600. 



7. (Natural size.) Cast of another pygidium. U. S. Nat. Mus., 



Cat. No. 70361. 



8. (Natural size.) Small pygidium doubtfully referred to the spe- 



cies. U. S. Nat. Mus., Cat. No. 70360. 

 Matrix, limestone. 

 Canadian ? Near Malad, Idaho. 



Xenostegium ? sulcatum Walcott 128 



Fig. 9. (X2.) Dorsal view of only cranidium discovered. U. S. Nat. 

 Mus., Cat. No. 70359. 

 Matrix, limestone. 



Ozarkian, St. Charles formation ?. (Loc. 55z) : Blacksmith Fork 

 Canyon, Utah. 



Xenostegium albert ensis Walcott 125 



Figs. 10, 11. (Natural size.) Dorsal and side views of the type pygid- 

 ium. U. S. Nat. Mus., Cat. No. 70362. 

 Matrix, limestone. 



Ozarkian, Mons formation. (Loc. 66v) : Upper Johnson Creek 

 Canyon, Sawback Range, Alberta, Canada. 



Xenostegium ? eudocia Walcott 126 



Fig. 12. (Natural size.) Central portion of the cranidium. U. S. Nat. 

 Mus., Cat. No. 70363. 

 Matrix, limestone. 



Ozarkian, St. Charles formation. (Loc. 55z) : Blacksmith Fork 

 Canyon, Utah. 



Xenostegium euclides Walcott 126 



Fig. 13. (X2.) Associated hypostoma which may belong to this spe- 

 cies. U. S. Nat. Mus., Cat. No. 70364. 

 14. (X 2.) Large and small pygidium. U. S. Nat. Mus., Cat. No. 

 70365. 

 Matrix, limestone. 



Ozarkian, Mons formation. (Loc. 66v) : Upper Johnson Creek 

 Canyon, Sawback Range, Alberta, Canada. 



