16 



bly a new species. In case other discoveries should prove it to be so, I 

 propose for it the name of P. vexaMlis. 



Breadth of the calyx, about eight millimeters ; height, five millime- 

 ters ; height from base to top of proboscis, two centimeters ; the arms 

 were capable of extending about one centimeter farther. 



Position and locality. Strata of Subcarboniferous age, Mountain 

 Spring, Old Mormon road, Nevada. 



Genus ACTINOCRINUS Miller. 



ACTINOCRINUS VIATICUS (sp. nov.}Body below the arms broadly 

 subturbinate ; arms slender, somewhat compressed laterally; apparently 

 thirty in all, since the two full rays and one-half of another that are in 

 view bear such proportionate numbers. The appearance of branching 

 of each ray begins below the periphery of the body, where, starting as a 

 single pair, they immediately bifurcate ; the two inner branches bifurcat- 

 ing again at or just beyond the periphery, the two outer branches remain- 

 ing simple. 



Surface of the body-plates marked by sharp, radiating ridges, which 

 give the whole surface below the arms a confused cancellated appear- 

 ance. 



Width of body at its periphery, about eighteen millimeters. 



Position and locality. Strata of the Subcarboniferous age, Mountain 

 Spring, Old Mormon road, Nevada. 



BEACHIOPODA. 

 Genus SPIRIGHERA d'Orbigny. 



SPIRIGERA MONTICOLA (sp. nov.) Shell subelliptical or subtetra- 

 hedral in outline, always wider than long, widest about the middle or a 

 little forward of it, moderately gibbous; convexity of valves nearly 

 equal ; postero-lateral margins thickened in old shells, but in younger 

 ones the whole margin is more or less sharp ; front margin only slightly 

 sinuous in very young shells, but very deeply sinuous in some old ones. 



Ventral valve broadly convex from side to side, regularly arching 

 from beak to front ; beak moderately prominent and slightly incurved ; 

 foramen as usual, round, rather small ; mesial sinus scarcely apparent 

 in young shells, but in some old ones becoming very deep at the front, 

 somewhat narrow, but moderately well denned at the sides. 



Dorsal valve gibbous in the umbonal region, prominent along the 

 middle, from which the sides slope away by gentle convex curves to the 

 lateral margins ; mesial fold in some specimens not well defined nor 

 very prominent, in which cases the valve has a broad convexity, but in 

 others the mesial fold is well marked, narrow, and very prominent at 

 the front of the shell, while in all it is hardly traceable behind the mid- 

 dle, even in adult shells. 



Surface of both valves marked by fine concentric lines or lamellae of 

 growth, and occasionally indications of fine radiating striae are to be 

 seen under the lens. 



Length of a mature specimen, twenty-three millimeters ; extreme 

 width, twenty-nine millimeters ; height, sixteen millimeters. 



Position and locality. Strata of the Subcarbouiferous period, Mount- 

 ain Spring, Old Mormon road, Nevada. 



Besides the foregoing new species, the collection also contains the fol- 

 lowing, which have heretofore been described from Subcarbonif- 



