BRACHI0P0DA — 0RTHID2E. 



267 



LVII. Schizophoria King. 

 Pedicle valve depressed convex, becoming slightly concave 

 toward the front. Brachial valve very convex. Hinge line short. 

 Cardinal areas moderately high. Plications rounded, hollow and 

 exceedingly fine. Muscular area of pedicle valve has elevated 

 margins and is deeply sunk in the substance of the shell. Shell 

 substance very punctate. This genus differs from Hebertella 

 principally in its much shorter hinge line and its punctate shell. 

 Siluric-Carbonic. 



A. Length exceeding breadth 210. S. macfarlani. 



B. Breadth exceeding length *, 



* Striae fasciculate, i. <?., in bundles 211. S. tioga. 



* Striae not fasciculate I. 



1. Hinge line quite long, forming nearly the greatest width of shell. Shell 



large, often exceeding I inch in width 212. S. swallovi. 



1. Hinge line equalling only about half the width of the shell a. 



a. Beak of pedicle valve prominent and pointed i / . 



1/. Beak of brachial valve not strongly arched, vascular impressions 



not bifurcating but diverging 206. .S". multistriata. 



1/. Beak of brachial valve strongly arched, vascular impressions not 



bifurcating, but parallel or converging 208. S. tulliensis. 



I / . Beak of brachial valve arched, vascular impressions bifurcating. 



207. 6. propinqua. 



a. Beaks of both valves about equal and not pointed 2'. 



2'. Cardinal areas narrow 213. S. resupinoides. 



2'. Cardinal areas moderately high ,.209. S. striatula. 



206. S. multistriata Hall. 



Of medium size. Ped- 

 icle valve with broad, 

 undefined sinus and 

 prominent, slightly in- 

 curved beak. Brachial 

 valve with obtuse beak. 

 Hinge line forming about 

 half the width of the 

 shell. Surface marked 

 by fine, equal, radiating 

 striae. Concentric growth- 

 lines very faint. Vascu- 

 lar impressions slightly 

 diverging forward but 

 not bifurcating. 



Helderbergian of New York. 



(Fig. 



Lower Devonic. 



Schizop/iona multistriata. (After 



