BEACHIOPODA. 



227 



Listr. 2 sp. R. psittacea, Labrador (low water?) Hudson's Bay, 100 

 fms. : Melville Id. Sitka; Icy Sea. B. nigricans, New Zealand, 19 fms. 



Fossil, 250 sp. L. Silurian — . N. and S. America, Europe, Thibet, 

 China. 



Sub-genera. ? Porambonites, Pander. P. aequirostris, Schl. Shell im- 

 punctate ; surface minutely pitted ; each valve with a minute hinge-area and 

 indications of two septa ; foramen angular, usually concealed. Distr. 4 sp. 

 L. Silurian. Russia, Portugal. 



Camarophoria, King. T. Schlotheimi, Buch. Figs. 141, 142. Ventral 

 valve with converging dental plates {d) supported on a low septal ridge {s) ; 

 dorsal valve with a prominent septum {s) supporting a spoon-shaped central 

 process {v) ; oral lamellse long and slender {o). Poramen angular, cardinal 

 process distinct ij). Fossil, 9 sp. ? Carb. — Permian (Magnesian limestone). 

 Germany; England. 



Fig. 141. Internal cast.'' 



Fisr. 142. Section. 



Pentamerus, Sowerby, 



Etym. Pentameres, 5 -partite. 



Syn. Gypidia (conchydium) Dalman. 



Type, P. Knightii, PL XV. fig. 22. Pig. 143. 



Shell impunctate, ovate, ventricose, with a large incurved beak ; valves 

 usually plaited ; foramen angular ; no area or deltidium ; dental plates {d) 

 converging, trough-like, supported on a prominent septum {s) ; dorsal valve 

 with two contiguous longitudinal septa {s s) opposed to the plates of the other 

 valve. 



Oral lamella have been detected by Mr. Salter in PJiratus; in P. ? bre- 

 virostris (Devonian, Newton) the dorsal valve has a long trough-like process 

 supported by a single low septum. 



Fossil, 20 sp. Arctic America, U. S. Em-ope. 



* Ventral side of cast, showing the V shaped cavity of the dental plates, and the 

 impressions of branchial veins, accompanied by arteries; (after King.) 



