32 BRITISH CRETACEOUS BRACHIOPODA. 



discovery of its complete interior will soon permit Palaeontologists to ascertain its true 

 position. It is possible that eventually it may turn out to be only a Terebratella} or have 

 a disposition of loop peculiar to itself, as we do not consider a beak being more or less 

 elongated of sufficient generic value. Many authors, however, seem disposed to separate the 

 shells in question from the true Terebratula?, and they may probably prove distinct. 

 Thus, Mr. Sowerby states that Mr. Cumberland had called it Lyra Meadi ; but, finding 

 the term Lyra so apt, he could not resist applying it to the specific name. Later (1825) 

 Kcenig, in his ' Icones Fossilium Sectiles,' placed it in his Triyonosemits, naming first, 

 T. elegans ; secondly, T. rustica ; and thirdly, T. lyra, as types and examples. All these, 

 however, have subsequently been placed in distinct genera, and we have preserved the 

 name of Triyonosemus to the first, which corresponds to M. D'Orbigny's genus Fisstcri- 

 rostra. Few authors, excepting Mr. Brown, 2 have applied Koenig's generic appellation to 

 T. lyra, and it was only in 1847 that M. D'Orbigny proposed his genus Terebrirosfra 3 

 In England, we are only acquainted with one species, the Terebrirostra lyra. 



12. Terebrirostra lyra, Sow. Sp. Plate III, figs. 17—28. 

 Encyclop. Moth. PI. 243, fig. 1, 1789. 



Terebratula lyra, Sow. Min. Con., vol. ii, p. 87, tab. 138, fig. 2, 1818. 



— — Lamarck. An. sans Vert., vol. vi, p. 255, No. 49, 1819. 



— — Conybeare and Phillips. Outlines of the Geol. of England and 



Wales, p. 130, 1822. 



— — Parkinson. An Introduction to the Study of Organic Remains, 



p. 234, 1822. 



— — Kcenig. Icones Fossilium Sectiles, p. 4, pi. vi, fig. 77, 1825. 

 Trigonosemus lyra, Koenig. Ibid., p. 4, pi. vi, fig. 76, 1825. 



Terebratula lyra, Smith. Strata identified by Organised Fossils, fig. 3, 1816 — 27. 

 (As this work appeared at different epochs, I do not know the 

 exact date of this species.) 



— — Defrance. Die. des Sc. Nat., vol. liii, p. 160, pi. Ixii, fig. 7, 1828. 



1 In the 'Journal de Conchiliologie,' No. 11, p. 223, 1851, M. D'Orbigny states his acquaintance 

 with five species of Terebrirostra, viz. T. neocomiensis, T. arduennensis, T. lyra, T. Bargesana, and T. cana- 

 liculata. Another most beautiful and well-characterised form, from the Chalk of Ciply, is known to me. 

 One of M. D'Orbigny's so-called species, the T. canaliculata of Rcemer, is a true Terebratella, and 

 somewhat resembles such species as T. Menardi and T. pectita, the loop is doubly attached, and disposed 

 exactly as we see in the types of the genus Terebratella. The position of the foramen relative to the 

 extremity of the beak is different from T. lyra and its associates ; and we cannot but feel surprised at 

 M. D'Orbigny proposing to place Rcemer's species in his genus Terebrirostra. 



2 ' Illustrations of Fossil Conch, of Great Britain,' 1838. 



3 ' Considerations Zoologiques et Geologiques sur les Brachiopodes,' 'Comptes Rendus Hebdomadaires de 

 l'Academie des Sciences,' Aout, 1847. 



