Maryland Geological Survey 163 



having been attached by the surface, which is maiked by concentric lines 

 varying in strength from striae to wrinkles and interrupted radiating 

 ridges which at intervals bear spine bases. The preserved ear is strongly 

 wrinkled and shows a conspicuous row of four spines just below the hinge- 

 line. It will be seen that the characters shown by this single valve agree 

 very well with those enumerated by Hall in his description of the species. 

 The specimen was submitted to Prof. Charles Schuchert, who reported it 

 to be " a Productclla and very probably P. spinulicosta." 



Length, 9 mm. ; width, 8 mm. 



Occurrence. — Romney Formation, Hamilton Member. Williams 

 Eoad I mile east of Queen City Hotel, Cumberland. 



Collection. — Maryland Geological Survey. 



PrODQCTELLA ( ?) SCHUCHERTI n. sp. 



Plate XIII, Fig. 21 



Description. — Shell of moderate size; hinge-line equaling the greatest 

 width of the shell. Ventral valve convex, the greatest convexity toward 

 the umbonal region; gradually sloping toward the front and lower lateral 

 margins, and abruptly depressed and flattened towards the cardino-lateral 

 margins. Surface marked by about 100 fairly large striae extending 

 almost to the cardinal extremities, which are slightly undulating and 

 increase by bifurcation. There are faint concentric striae and an occa- 

 sional wrinkle or lino of growth. 



The specimens of this species consist of an imperfect ventral valve and 

 a fragment of another valve; but as it probably carries a form related to 

 the groui> Lineati of the Carboniferous Productus, back into the Middle 

 Devonian, it is thought worthy of description. The specimens were sub- 

 mitted to Dr. J. M. Clarke and Prof. Schuchert. Dr. Clarke said that 

 they suggested Productclla of the Carboniferous. Prof. Schuchert wrote 

 as follows : " These are not Chonetes since there are no hinge spines nor 

 indications of shell punctures. The general form, striae and concentric 

 markings indicate Productus of the type of P. cora. If this is so it is 

 very interesting in extending the line of this prominent group of Pro- 

 ductus. This type of Productus begins M-ell developed in the Kinder- 



