17 



erous strata, and to which period I have referred the rocks from which 

 the specimens were collected. The first line gives the localities of the 

 specimens contained in the collections, and the second those Subcarbon- 

 iferous localities which furnished the types of all the species named ex- 

 cept one. 



Syringopora Harveyi White ? 



Ewell's Spring, Arizona. 



Burlington limestone, Burlington, Iowa. 

 Productus Parvus Meek and Worthen. 



Mountain Spring, Old Mormon road, Nevada. 



Chester limestone, Chester, Illinois. 

 Strophomena rhomboidalis* Wilckins. 



Mountain Spring, Old Mormon road, Nevada. 



Kimlerhook formation of Illinois and Iowa and elsewhere. 

 Spirigera obmaxima McCbesney. 



Mountain Spring, Old Mormon road, Nevada, and below Ophir 

 City, Utah. 



Keokuk litoestone of Iowa and Illinois. 

 Spirifer (Martinia) peculiar-is Shrunard. 



Mountain Spring, Old Mormon road, Nevada. 



Kinderhook, formation of Missouri and Iowa. 

 Spirifer centronata Winchell. 



Mountain Spring, Old Morman road, Nevada. 



Waverly sandstone, Cuyahoga Falls, Ohio. 

 Spirifer striatus Martin. 



Mountain Spring, Old Mormon road, Nevada. 



Burlington limestone (j$. Grimesi), Burlington, Iowa. 

 Spirifer ( Sy r ingot hyr is) extenuatus Hall. 



Mountain Spring, Old Mormon road, Nevada. 



Kinderhook formation of Iowa and Missouri. 

 Terebratula Burlingtonensis White. 



Mountain Sprirg, Old Mormon road, Nevada. 



Kiuderhook formation, Burlington, Iowa. 

 Proiuctus Prattenianus Norwood (=? P. Icevicostus White). 



Below Ophir City, Utah. 



Kinderhook formation, Burlington Iowa (P. Icevicostus). 

 Orihis Michilini var. Burlingtonensis Hall f 



Below Ophir City, Utah. 



Burlington limestone, Burlington, Iowa. 



CARBONIFEROUSf PERIOD. 



ECHINODEKMATA. 

 Genus ARCHJEOCIDARIS McCoy. 



ARCH^SOCIDARIS TRTJDIFER (sp. nov.) Interambulacral plates com- 

 paratively broad, rather thin, with a row of small tubercles forming an 

 elevated border all around ; areolar surface apparently plain ; central 

 tubercle small, perforated in the center, surrounded at its base by a 



* Almost world-wide in its distribution, but is believed not to exist in strata of later date 

 than the Subcarbonit'erous. 



tl use this term to indicate all the strata between the Subcarboniferous below and the 

 Permian above, and especially in contradistinction to the Subcarboniferous ; in other words, 

 it is used as synonymous with the general term " Coal-Measures," somewhat in use. 

 2 I F 



