320 SYSTEMATIC PALEONTOLOGY 



Genus COLEOLUS Hall 

 COLEOLUS IOWENSIS James 

 Plate XLIX, Figs. 22, 23 

 Coleolus iowensis James, 1890, Amer. Geol., vol. v, p. 355. 



Description. This species has never been illustrated, but it has been 

 known for many years as a very abundant fossil in the Maquoketa shale 

 of Eichmond age in Illinois and Iowa. It occurs here in great numbers 

 associated with Cyclora minuta and similar small gastropod shells, as well 

 as such minute pelecypods as Ctenodonta obliqua, and Clidophorus. The 

 shell layer is seldom preserved, the species occurring almost invariably as 

 phosphatized casts of the interior. The surface markings of the outer 

 shell are occasionally preserved as molds of the exterior in which it may be 

 noted that the shell surface is smooth or sometimes very minutely annu- 

 lated. The shell itself is an elongate, gradually tapering, straight or 

 slightly curved cone, 15 to 20 mm. long and a millimeter in diameter at 

 its widest portion. The diameter and length of different examples of the 

 species vary considerably, indeed quite frequently these fossils occur only 

 as broken fragments. 



Occurrence. MARTINSBUEG SHALE (Sinuites bed). Chambersburg, 

 Pennsylvania. 



Abundant in the Mohawkian and Cincinnatian rocks of Iowa, Illinois, 

 and many other states, the types coming from the Maquoketa shale division 

 of the Richmond group of Iowa. 



Collections. Maryland Geological Survey, U. S. National Museum. 



Family CONULARIIDAE 



Genus GONULARIA Miller 

 CONULAHIA TKENTONENSIS Hall 



Plate L, Fig. 42 



Conularia trentonensis Hall, 1847, Nat. Hist. New York, Pal., vol. i, p. 222, 



pi. lix, figs. 4a-f. 

 Conularia trentonensis Weller, 1903, Geol. Surv. New Jersey, Pal., vol. iii, 



p. 188, pi. iii, figs. 7, . 



Description. " Shell of medium size, pyramidal in form, quadrangular 

 in cross-section, the sides diverging from the apex at an angle of about 



