﻿CRETACEOUS BRACHIOPODA. 55 



Most of the examples that have fallen under my observation were either nearly 

 circular or slightly elongated oval, with a greater or lesser depression in the anterior 

 portion of the dorsal valve ; this depression becoming very small, and even almost 

 obsolete, in some specimens. 



Position and Locality. — Wald. Walkeri occurs rather abundantly in ironstone beds, 

 referred by Mr. Judd to the Middle Neocomian, at Acre House, near Tealby, in Lincoln- 

 shire. A fine series of specimens collected by Mr. Judd may be seen in the Museum of 

 the Geological Survey, also in the Woodwardian Museum, Cambridge. M. Geny and 

 myself found specimens agreeing with those that occur at Acre House, in beds of about 

 the same age, at Papaton and Braus, near Nice, in the South of France. 



69. Waldheimia faba, a" Orb. sp. Sup., PI. VI, figs. 12 — 14«. 



Terebratula longa, Roemer. Ool.-Geb., p. 22, pi. xviii, fig. 12 (from the Hils), 



1836. 



— — — Kreide-Geb., p. 44, 1841, 



— faba, cTOrbigny. Pal. Franc;., Terrain Cretace, p. 77, pi. 506, figs. 8 — 



12, 1847 (not Tereb.faba, Sow.). 



— — Credner. Zeitsch. der Deutsch. Geol. Ges., p. 563, pi. xxviii, 



figs. 3, 4, 5 (from the Hils), 1864. 



— longa, Quenstedt. Die Brachiopoden ; Pet. Deutscliland's p. 338, pi. 



xlvi, figs. 99, 100, 1871. 



— (Waldheimia) faba, Pictet. Brachiopodes du Terrain Cretace de Ste.- 



Croix, p. 92, pi. cciii, figs. 9, 10, 

 1872 (not T.faba, Sow.). 



Spec. Char. — Shell longitudinally oval, broadest anteriorly, tapering to the beaks, 

 nearly straight in front ; valves almost equally convex, and deepest near the umbo. 

 Ventral valve moderately convex, beak slightly incurved and truncated by a foramen of 

 smallish dimensions, partly margined on either side by a deltidium in two pieces ; beak- 

 ridges sharply defined, leaving a concave space between them and the hinge-line. 

 Dorsal valve either uniformly convex or flattened, and slightly concave anteriorly ; front- 

 line straight or moderately curved. Surface smooth, marked at intervals with concentric 

 lines of growth. Average proportions : 



Length 13, width 2, depth 9 lines. 



Obs. — Alcide d'Orbigny, Pictet, and others are, 1 think, mistaken when they refer 

 the Tereb. {Waldheimia) longa of Roemer to the Tereb.faba of Sowerby. I still consider 

 this last to be a young Terebratula biplicata, derived from the Upper Greensand of 

 Warminster, the original specimen being preserved in the Museum of the Geological 



