NO. 3 CAMBRIAN TRILOBITES 24I 



PAGE 



Crepicephalus liliana Walcott 209 



Fig. S. (Natural size.) Cranidium with graiiulose surface. U. S. 

 National Museum, Catalogue No. 15428. 

 Sa. (Natural size.) Pygidium associated with the specimen repre- 

 sented by fig. 5 in the same fragment of rock. U. S. 

 National Museum, Catalogue No. 15428. 

 Sb. (Natural size.) Cranidium from another locality. U. S. 



National Museum, Catalogue No. 61640. 

 5f. (Natural size.) Free cheek associated with the cranidium 

 of 5b. U. S. National Museum, Catalogue No. 61641. 



The specimens represented by figs. 5 and 5a are from 31a, Lower 

 Cambrian : Pioche formation, near Pioche, Nevada. 



The specimens represented by figs. 5& and 5c are from (30) 

 Lower Cambrian : limestone on west slope of Highland Range, 

 Smiles (12.8km.) north of Bennetts Spring, Nevada. 



These figures are illustrated in the Tenth Annual Report, U. S. 

 Geol. Survey, 1890, plate 96, figs. 7, ya-c. 



Crepicephalus augusta Walcott 204 



Fig. 6. (X4-) A small cranidium, showing variation of form from 

 that represented by fig. 6a. U. S. National Museum, Cata- 

 logue No. 61642. 

 6a. (Natural size.) Broken cranidium showing form of frontal 



border. U. S. National Museum, Catalogue No. 61643. 

 6&. (Natural size.) Pygidium with right side partly restored. 

 U. S. National Museum, Catalogue No. 15430. 



The two cranidia represented by figs. 6 and 6a are from (30) 

 Lower Cambrian: limestone on west slope of Highland Range, 

 8 miles (12.8 km.) north of Bennetts Spring, Nevada. 



The specimen represented by fig. 6b is from (31a) Lower Cam- 

 brian : Pioche formation, near Pioche, Nevada. 



Specimens of the pygidium also occur in locality 30. 



These figures are illustrated in the Tenth Annual Report, U. S. 

 Geol. Survey, 1890, plate 96, figs. 9, ga-b. 



Crepicephalus texanus (Shumard). (See pi. 30) 209 



Fig. 7. (Natural size.) Cranidium with occipital ring restored, and 

 associated specimen. U. S. National Museum, Catalogue 

 No. 61644. 



From locality 151!, Gallatin limestone; northeast of White 

 Sulphur Springs, Meagher County, Montana. 



