OF CONCHOLOGY. 



141 



Bouchardia, Dav., Bull. Soc. Geol. de France, vol. vii, 1849, 

 p. 62, pi. i. ; An. Nat. Hist. 1852, p. 372. King, Perm. 

 Foss. p. 81, 1850. Gray, B. M. Cat. p. 100. H. and 

 A. Adams, Gen. Rec. Moll, ii, p. 557. Chenu, Man. de 

 Conchyl. ii, p. 207. Woodw., Rec. and Foss. Shells, p. 

 218. Rve., Conch. Icon. pi. viii ; Journ. de Conchyl. 

 1861, p. 130. Dav., Int. Brit. Brach. p. 70; An. Nat. 

 Hist. 1861, p. 38. 



Shell with a nearly straight beak, apically foraminated with a 

 small circular perforation. No true area or deltidium. Hinge- 

 plate large, solid, provided with ^-shaped diverging ridges, pro- 

 bably for the attachment of the cardinal muscles. Socket 

 ridges of the hferaal valve largely developed, and fitting into 

 corresponding furrows in the neural valve. There is no cavity 

 beneath the hinge-plate ; from its base a not prominent median 

 septum arises, reaching beyond the middle of the shell, and 

 bearing two pointed, lateral, posteriorly recurved processes. 

 Muscular scars in the neural valve, subcentral and divided by a 

 mesial ridge. 



Fig. 19. 



Fig. 19. Bouchardia tulipa, interior of both valves. /, foramen ; (f, delti- 

 dium ; t, dental sockets ; r, cardinal scars ; a, adductor scars ; /', peduncular 

 muscle scars ; «, septum ; I, lateral processes of septum. 



Tt/pe. Bouchardia tidipa^ Blainv., fig. 19. 



Terehratula tidipa, Blainv., Diet. Sci. Nat. liii, p. 144, 1828. 



Terehratula rosea, Mawe, Int. to Conch. 1823 ? Sby., Gen. 



fig. 4 ; Thes. Conch, vii, p. 357, pi. Ixxi, figs. 74, 75, 76, 



77. Deshayes, in Lam. 2nd. Ed. Hist, des An. s. Vert. 



vii, p. 350. King, An. and Mag. Nat. Hist. 1846, pp. 



34, 38. 

 T. unguis, Kuster, Conchyl. Cab. vii, p. 35, fig. 8 — 10, 1842. 

 PachyrhyncJius roseus, King, Perm. Foss. p. 70. 

 Bouchardia rosea, Dav., Bull. Soc. Geol. de France, vol. vii, 



p. 62, pi. i, figs. 1 to 6. King, Perm. Foss. p. 81. 

 Bouchardia tulipa, Dav., 1851, Int. Brit. Brach. p. 70, figs. 



17, 18, pi. vi, figs. 22—25. Woodw., Rec. and Foss. Sh. 



p. 218, fig. 118. Gray, B. M. Cat. p. 101, figs. 13, 14. 



