157. CONTRIBUTION TO 



are three septal fossettes, the principal one is situated on the anterior side; the 

 two secondary ones are at right angles to the primary one. Situated in the 

 principal fossette is one large lamellae, extending from the bottom of the calix 

 to the anterior margin. Situated on either side of the single large lamelhe is 

 three shorter ones. The surface is comparitively smooth, with a few wrinkles 

 and shallow constrictions. Longitudinal striae fine, distinct. 



Found in the Middle Devonian (Upper Helderberg group) at the Falls of 

 the Ohio. Now in the collection of the author. 



HELIOPHYLLUM VESICULATUM. 



Plate 46. Figs. 7, 8, 9, 10, 11, 12. 



Example Cyathophyllum vesieulatum, Hall. Thirty-fifth Annual Report of the New York 

 State Museum of Natural History. Advance sheets, August, 1882. 



Cyathophyllum vesieulatum, Hall. Indiana Geological Report Page 297, Plate 23, Figure 6, 



1882. 



Corallum, simple, turbinate, straight, or slightly curved, usually having a 

 small scar at the point of attachment. Height varying in different individuals, 

 from ten to thirty millimeters. Calix thin and broadly bell-shaped, from fifteen 

 to twenty-five millimeters in diameter. Depth fifteen millimeters. Number of 

 lamellffi sixty, in the circumference of a calix twenty millimeters in diameter, 

 unequal in size at the margin, alternating below, for about five millimeters 

 gradually then they rapidly slope to the bottom of the calix, giving the calix 

 somewhat of a funnel-shaped appearance. Fossette consists of a slight depres- 

 sion in the bottom of the calix but does not extend on the side of the cup. Den- 

 ticulations well defined, in well preserved examples. 



Found in the Middle Devonian (Upper Helderberg group) at the Falls of 

 the Ohio. The examples illustrated are in my collection. 



DOLATOCRINUS CORPOROSUS? M. & G., Rowley. 



Plate 47. Figs. 1, 2, 3. 



The specimen before us differs some from D. eoi'porosus in ornamentation, 

 but still more in the number of arms, having but tei/'^against twenty in that 

 species, a difference partly accounted for in the absence of one entire arm group 

 in our specimen. 



The four- rayed character of this fossil gives rise to broad and deep ventral 

 inter-anibulacral areas and a strongly lobed ventral aspect. 



On the dorsal side this same irregularity so disturbs the usual plate ar- 

 rangement that a large, well defined anal area exists, the first plate of which 



