EARLY DEVONIC HISTORY OF NEW YORK AND EASTERN NORTH AMERICA I05 



Cyrtoceras albani nov. 



Plate 13, figures 6, 7 



This is a quite common shell in these beds, having a long slender and 

 gently curved cone, broadly swollen on the body chamber and constricted 

 behind the aperture. The greatest curvature is in the later parts of the 

 shell, the earlier portion being quite straight for a short distance. The 

 septa are regularly concave and close together, the surface ornamented by 

 very fine elevated threadlike eccentric lines. The species is not unlike 

 the Cjrtoceras subrectum Hall of the Helderbergian, whatever 

 generic form that may prove to be when better known. 



Locality. In the lower beds, Cape Rosier Cove. 



Conularia lata Hall niut. 



See p. 144 



Forms agreeing with those assigned to this species from the higher 

 strata occur in lower beds of Cape Rosier Cove. 



Probolaeum ? canadense nov. 



Plate 17, figures 1,2 



We are disposed to regard as a representative of the Polyplacophora 

 or chitons an elongated semicone-shaped plate sinuate on its front margin, 

 with a posterior terminal beak and broadly enfolded posterior margin. The 

 characters of this plate are shown in the figures drawn from a sculpture 

 cast, displaying the sharp concentric growth lines which are crowded 

 together on the enfolded part of the test. The length is 28 mm and the 

 anterior width 19 mm. 



In the Devonic of the Appalachian gulf no chitons have been found, 

 though these bodies are known from several horizons in the transatlantic 

 Devonic. There is noteworthy similarity in the form and aspect of P. 

 canadense to Chiton sagittalis Sandberger (Stringocephalus 

 limestone).' 



Locality. Cape Rosier Cove. 



Pleurotomaria labrosa Hall 



Plate 16, figure i8 



Pleurotomaria labrosa Hall. Palaeontology of New York. 1859. 3:339, 

 pi. 66, fig. r-5 ; pi. 67, fig. 6 



This Striking and rather remarkable species which has not before been 

 found outside of the Helderbergian (Becraft and New Scotland limestones) 



' Verstein. rhein. Schichtensys, p. 239, pi. 26, fig. 23. 



