628 Systematic Paleontology — Upper Devoxiax 



Occurrence. — Jennings Formation, Parkhead Member. Four miles 

 southeast of Pratt on White Sulphur Branch. 

 Collection. — Maryland Geological Sun'O}'. 



Superfamily PTERIACEA 

 Family PTERINEIDAE 



Genus PTERINEA Goldfuss 

 Pterinea nodocosta n. sp. 



Plate LXI, Figs. 19-21 



Description. — Shell of medium to large size, suberect, scarcely oblique. 

 Body broad, subtransverse in front. Anterior wing small ; posterior wing- 

 broad and acute but not greatly extended. Surface with 4-5 very strong 

 radii, nodose at distant intervals. Between these radii lie others of vari- 

 ous or alternating size, 3-5 in each interval over the shell body. On the 

 posterior wing the radii are obscure and subequal; the anterior wing is 

 also plicate. Strong concentric striae cover the marginal parts of the 

 shell. Of an average individual, height and hinge-length 62 mm. ; width 

 "across the body 55 mm. 



Prof. Hall figured in Paleontology of New York (vol. v, pt. i, pi. 

 Ixxxiii, fig. 11) a large shell from the Chemung beds which he referred to 

 Pterinea flabella Hall of the Hamilton fauna but which has characters 

 very similar to those here described. The size, suberect form and the 

 nodate or subnodate character of the princapal radii are features in 

 which this later shell differs from P. flabella. The single example show- 

 ing the exterior given by Hall does not indeed represent the major ribs 

 as distinctly nodate but the specimen has been corroded by exposure and 

 in its original condition was probably similar in structure to that here 

 described. 



Occurrence. — Jennings Formation, Chemung Member. Oakland- 

 Altamont Road; E. Gordon's farm 1 mile northeast of Mountain Lake 

 Park; northeast edge of Deer Park; 2 miles south of Oakland. 



Collection. — Maryland Geological Survey. 



