﻿JURASSIC AND TR1ASSIC BRACHIOPODA. 



93 



pointed beak, perforated at its extremity by a small circular aperture or foramen. 

 Ventral valve uniformly convex, beak almost straight ; dorsal valve concave, following the 

 curves of the opposite one : hinge-line narrow, area of the larger or ventral valve 

 triangular, long, and narrow, giving the shell a peculiar straight-beaked appearance. 

 Deltidium triangular. Surface of valves marked by a multitude of exceedingly fine 

 radiating or longitudinal lines, visible only by the aid of a good lens. 

 Length one or two lines, width less. 

 Ohs. This minute species is at once distinguishable from Lepttena Bouchardii by its 

 elongated, straight, narrow beak, truncated and pierced at its extremity by a circular 

 aperture, which does not appear to exist in L. Bouchardii. It was first discovered by 

 Mr. E. Deslongchamps in the Lias of Fontaine-Etoupe-Four in Normandy, and since then 

 three examples were found by Mr. C. Moore in the Middle Lias of Whatley and Munger ; 

 none of the specimens quite attained a line in length. 



29. Lept.<ena liasiana, Bouchard. Dav., Ool. Mon., p. 18, PI. I, fig. 21. 



Lept/ENA liasiana, E. Desl. Memoires de la Soc. Linn, de Normandie, vol. ix, pi. xi, 



figs. 3 and 4, 1853. 



This interesting little species is rare in the Upper Lias of Ilminster, but more abundant 

 in that of May, near Caen, in Normandy. See also our remarks at p. 15 of the Appendix 

 to vol. i of this work. 



30. Lept^na Moorei, Dav. Dav., Ool. Mon., p. 17, PI. I, fig. 18. 



Nothing new to be added. It occurs in the Upper Lias or zone of Am. bifrons. 



31. Lept,ena Pearcei, Dav. Dav., Ool. Mon., p. 17, PI. I, fig. 19. 



Since the publication of my description in June, 1851, Mr. Moore has referred this 

 shell to the genus Monotis. It must consequently be removed from the Brachiopoda 

 to the Lamellibranchiata, as will be found stated at p. 15 of the Appendix to vol. i of 

 this Monograph. 



