80 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.51. 



Fig. 24. Mold of the exterior of a piece of a brachial valve enlarged two 

 diameters to show the fine concentric lines crossing the plications and the 



■ distinct median furrow on the fold. 



Formation. — Edmunds formation of the Silurian. 



Locality. — West shore of Cobscoolj River, about half a mile south of 

 Bells Mountain, Edmunds township, Washington County, Maine. 



Spirifer edmundsi Williams. 



Fig. 13. Mold of the exterior of a pedicle valve. The drawing was made 

 from an impression of the opposite side of same specimen represented by 

 figure 15 and shows the plications more in number than in S. cobscooki 

 (see fig. 10). 



Fig. 14. Mold of the interior of a brachial valve, showing the plications and 

 furrow along the top of the fold. 



Fig. 15. Mold of the interior of same specimen represented by figure 13. 

 showing the relatively low area and the absence of a .median septum. 



Formation. — Edmunds formation of the Silurian. 



Locality. — West shore of Cobscook River, about half a mile south of Bells 

 Mountain, Edmunds township, Washington County, Maine. 



Spirifer luhecensis Williams. 



Fig. 16. An end view of a pedicle valve, showing the high, pointed beak and 



nearly straight cardinal area. 

 Fig. 17. Mold of the interior of a pedicle valve, showing the plications, the 



broad shallow median sinus, and the angular beak with its nearly straight 



sides. Another view of same specimens as figure 1. 

 Figs. IS and 19. Two views of another specimen, showing the cardinal area, 



delthyrium, and slightly overarching beak. 

 Figs. 26 and 28. Two specimens of brachial valves, both of them imperfect 



and distorted by crushing of rock after they were imbedded. 

 Fig. 27. The exterior surface of a pedicle valve, faintly exhibiting surface 



sculpture of concentric lamellose lines. 

 Formation. — Edmunds formation of the Silurian. 

 Locality. — Lubec township, Washington County, Maine. 



