208 NEW YORK STATE MUSEUM 



face sculpture consists of closely crowded subequal rounded riblets, 

 alternation of size being noticeable near the margins. 



Loiver Devonic. Presque Isle stream, Chapman Plantation, 

 Matagamon lake and elsewhere, Me. 



Pterinea ? mytiloides nov. 



A Leptodesmalike shell, extremely oblique and elongate with a 

 subacute anterior extremity, anterior beak, short hinge, oblique 

 broadly rounded umbonal ridge terminating in a broad blunt pos- 

 terior extremity. The lower margin of the valve makes at the 



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Pterinea ? mytiloides 



anterior extremity an angle of about 40 degrees with the hinge, is 

 slightly incurved by the broad and obscure cincture in front of the 

 umbonal ridge. 



Dimensions. The best preserved example has a length from 

 anterior end to postlateral curve of 25 mm ; hight from the beak 

 7 mm ; greatest hight 12 mm. 



This species is provisionally referred to Pterinea and it is more 

 than doubtful if it has any immediate relations with Leptodesma 

 Hall in the sense in which that name was employed by its author. 

 Its age and surroundings indicate that it has direct pterineoid 

 affinities. The shell is rare but its form leads to its ready 

 recognition. 



Lower Devonic. Dalhousie, N. B. 



Pterinea brisa nov. 



An elongate shell, quite erect, the axis of growth being essentially 

 at right angles to the hinge. The body is produced and moderately 

 expanded ; the wings distinctly developed but not large, the posterior 

 being narrow, the anterior short and the byssal sinus well defined. 

 The length of the hinge in the specimen before us is 32 mm, the 

 vertical hight 40 mm. The beak is at the anterior third of the 

 hinge. The surface is marked by radial elevated lines with broad, 

 flat interspaces, broken by intercalated lines of minor series. In the 



