THE BRITISH FOSSIL BRACHIOPODA. 269 



28. Waldheimia cor, Lamarck (?). Dav., Appendix to Supplements, Vol. V, PI. 



XIX, figs. 16, 16*. 



Terebratula cor, Lamarck. Animaux sans vertkbres, vol. vi, p. 249, 1819. 



— — Befrance. Die. des Sciences Nat., vol. liii, No. 8, p. 151, 1832. 



Rehmahni, De Buck. Die Versteinerungen des Oolithen-Gebirges, 



tab. xviii, fig. 11, 1839. 

 cor, Dav. Examination of Lamarck's Species of Terebratula, Annals 

 and Mag. of Nat. Hist., p. 5, pi. xv, fig. 22, 1850. 

 Zeillerta cor, Bayle. Explication de la Cart. Geol. de France, vol. iv, Atlas, pi. ix, 

 fig. 4, 1S78. 



Shell subpentagonal, nearly as wide as long, broadest about the middle. Valves almost 

 equally convex, most so anteriorly, lateral margins rounded, indented in front. Dorsal 

 valve regularly convex to about half its length, when a median depression commences 

 and extends to the front. Ventral valve convex to about its middle, when a similar 

 depression as seen on the dorsal valve extends to the front ; front line almost straight ; 

 beak moderately incurved, and truncated by a small circular foramen, margined laterally 

 by deltidial plates ; beak ridges sharply defined. Surface smooth, marked by concentric 

 lines of growth ; loop long. 



Length 12, breadth 13, depth 8 lines. 



05s. — Lamarck, in 1819, describes this species as follows: — " T. testa cordiformi 

 subglobosa, supra sinu valde exarata, striis tenerrimis decussatis." No reference to figure, 

 locality, or age of deposit is given by the author, so that much doubt rested on this 

 species until M. Valenciennes found in the collection of the Jardin des Plantes the type 

 specimen, which he forwarded to me, and of which I gave an exact figure in the 

 ' Annals and Magazine of Nat. Hist.,' 2 ser. vol. xv, 1850, pi. xv, fig. 22. For long I 

 could not divest my mind of the idea that it was only a form of Wald. numisutalis, 

 but M. E. Deslongchamps is of opinion that the two species, although nearly 

 allied, can be distinguished. He says : " Notwithstanding its extreme variation, 

 T. cor is easily distinguishable by its out-spread shape, truncated or bi-lobated 

 front, and strong posterior angularity, by its depressed valves near the beaks, and 

 gibbosity towards the front. Its very small foramen distinguishes it from other Tere- 

 bratulse with which it might be confounded, except the T. numimalis and indentata ,■ 

 but the first is nearly always nearly flat and is never inflated anteriorly, and but little 

 indented." He admits that the shell varies in an astonishing manner, and is sometimes 

 flattened, as in W. numismalis, and, indeed, I am not yet satisfied that they are more 

 than variations in shape of a single type. As Mr. Deslongchamps and many others 

 separate the two under distinct names, I have provisionally followed them in this sup- 

 position ; and, indeed, if we are to draw up descriptions from extreme shapes, a difference 



