CLASS II 



BRACHIOPODA 



383 



BiloUtes Linn. (Dicoelosia King) (Fig. 564). Silurian and Lower Devonian ; 

 Europe and North America. 



Schizophoria King (Fig. 565). Relative convexity of valves reversed. 

 Large, very finely striate, with the Striae hollow and spinöse! Cardinal 



Fk;. 565. 

 A-C, Schizophoria striatula (Schloth.)- Devonian ; Gerolstein, Eifel. A, Dorsal aspect. B, Interior of 

 dorsal valve. C, Interior of ventral valve. D, S. vulvaria (Schloth.). Spiriferensandstein (Lata Lower 

 Devonian) ; Niederlahnstein, Nassau. Internal mould. (All tigures of the natural size.) 



process in mature shells with accessory ridges making it multilobate. Dorsal 

 interior marked by 4 to 6 deep pallial sinuses. Silurian to Goal Measures ; 

 widely distributed throughovit the world. Subgenus : Orthotichia Hall and 

 Clarke. Like Schizophoria externally, but in the ventral valve the dental 

 lamellae and a median septum are highly developed. Goal Measures ; Brazil 

 and India. 



Subfamily C. Enteletinae Waagen. 



Rhipidomellidae with decidedly convex valves and a few hroad plications super- 

 added to the very fine radial Striae. Developed out of Orthotichia. 



Enteletes Fischer {Syntrielasma Meek and Worthen). Dorsal valve more 

 convex than ventral. Hinge-line short with a high ventral cardinal area. In 

 the ventral valve the dental lamellae are high and convergent, and between 

 them is a marked median septum ; the crural septa of the dorsal valve are 

 also well developed. Goal Measures and Permian ; North and South America, 

 Europe and Asia. 



Enteletoides Stuckenberg. Upper Garboniferous ; Russia. 



Superfamily 2. STROPHOMENACEA Schuchert. 



Progressive, terminal Protremata, derived out of Orthacea (Billingsellidae), with- 

 out spondylia and cruralia. Deltidia and chilidia nearly always present throughout 

 life ; cardinal process always well developed. Pedicle nearly always small, emerging 

 through the apex of the valve, or lost when the shells cement toforeign objects or anchoi' 

 by means of ventral spines. A prolific stock of Brachiopods. Ordovician to Recent. 



Family 1. Strophomenidae King. 



Primitive Strophomenacea with well -developed deltidia and chilidia. Shells 

 usually ßat or concavo-convex and but rarely biconDex. Pedicle usually functional 

 but tending to be thin and weak, and often lost when the shells cement to foreign 

 objects or are otherwise held to the substratum {usually by spines). Ordovician to 

 Permian. 



