SOME NEW DEVONIC FOSSILS 



219 



posterior slope and rather straight posterior margin. Length 

 about twice -the hight ; actual length of a full sized example 60 

 mm, hight 35 mm. Surface with concentric lines only. 



Lower Devonic. Moosehead lake, Baker Brook point and 

 Matagamon lake, Me. 



Modimorpha vulcanalis nov. 



Shell robust, with very thick valves ; outline short, obliquely 

 cordate, hinge line oblique, beak in front of the middle, not ele- 

 vated; umbonal ridge low but distinct from which the slope an- 

 teriorly is broad and very gently convex while posteriorly it is 

 at first gently concave, then depressed and almost flat near the 

 hinge line. The marginal outline is narrow in front at the ex- 



Modiomorpha vulcanalis 



tremity of the oblique hinge, widens in a low curve backward, 

 turns almost at right angles at the end of the crescence line, curv- 

 ing thence broadly upward and forward, joining the obliquely 

 elevated hinge in a broad curve. The length and width of the 

 shell are nearly the same. 



The resemblance of this species to Drevermann's Goniophora 

 c o g n a t a^ is very close in all visible features save that the 

 crescence ridge in the latter is somewhat sharper. It may also 

 be compared to I\'I. e 1 e v a t a Krantz of the lower Coblentzian.^ 

 Professor Kayser suggests a similarity with M. s i e g e n e n s i s 



'Fauna d. Untercoblentzsch. 1902. p. 88, pi. to, fij:. 15, 16. 

 2Beushausen. Latnell. d. rhein. Devons. p. 23, pi. 2, fig. 9-1 1. 



