oe oe eee ee ——_— 
VOL. XV. (2) C. UPTON—BRACHIOPODA 83 
R. subangulata, as described by Dr T. Davidson, and 
figured by him,’ there are at least two other well-defined 
species, which I will now describe. 
I. RHYNCHONELLA GRANULATA, sp. nov. 
Pl. IIl., figs. 1—6. 
DIAGNOsIS.—Shell of medium size, somewhat triangular, usually 
wider than long; valves moderately convex; the con- 
vexity of the brachial valve exceeding that of the pedicle 
valve, umbo prominent; distinctly trilobed, central lobe 
considerably elevated with a correspondingly deep sinus 
in the pedicle valve; beak acute, slightly incurved ; beak 
ridges sub-acute, forming considerable false areas ; foramen 
small, circular, margined, complete, separated from the 
umbo by well-displayed deltidial plates; ribs prominent, 
angular, extending the entire length of shell, usually from 
sixteen to eighteen in number, of which four or five occupy 
the mesial fold ; flanks of the ribs covered by innumerable 
small granules. The valves meet in front at an acute 
angle, but at maturity become thickened by the addition 
of numerous parallel layers of shell on the inner margins. 
Three specimens measure as follows :— 
Length... on 15 Mim. (16mm. 19 mm, 
Width ... oe 2 mM, 21 Mmm. 19 mm, 
Height ... aS) i.) FS Ti... 52 nae 
A more globose variety occurs having more numerous 
ribs and a less defined mesial fold. : 
Dr Haas, in his monograph on the Ahynchonelle of the 
Jura formation of Elsass-Lothringen, pl. 5 fig. 3, figures a 
specimen of that genus from the Murchisonaeschichten of 
St Quentin bei Metz as #. cf. angulata (Sowerby), which 
_may be the same shell, but in the specimen figured the 
foramen is incomplete. — 
R. granulata differs from FR. subangulata in having a 
granular surface to the valves, in the continuous convexity 
r Suppl. Brit. Juras. Brach. (Pal. Soc.), Vol. iv., p. 208, pl. xxix., figs. 14-16. 
