Val. 58.] BRACHIOPODA OF THE MALVERN HILLS. 143 
Acrorrera (?) Sasrinz (Callaway). 
1877. Obolella Sabrine, Callaway, Quart. Journ. Geol. Soc. vol. xxxiii, p. 669 & 
pl. xxiv, fig. 12. 
1883. Obolella Sabrine, Davidson, ‘ Brit. Silur. Brach. Suppl.’ Monogr. Paleont. 
Soc. p. 211 & pl. xvi, figs. 27 & 28. 
Several specimens found in Grey Shale, in company with Lingu- 
lella Nicholsoni, are in close agreement with examples from the 
Shineton Shales. It has been suggested! that this species, previously 
described as an Obolella, is an Acrotreta, though the pedicle-valve 
is much less elevated than in typical members of the genus, nor has 
the pedicle-furrow been observed. 
ACROTRETA(?) SABRINA, Var. MALVERNENSIS nov. (Figs. 11-14.) 
Shell smail, rather wider than long, or as long as wide, in out- 
line subcircular, but somewhat truncated posteriorly by a straight 
hinge-line, whose width is about two-thirds of the greatest width 
of the valve. 
Figs. 11-14.—Acrotreta (?) Sabrine, var. malvernensis nov. 
(From the Lowest Black Shales. Prof. Groom’s Collection.) 
iia. 1) 0. 
Fig. 1i w= Internal east of pedicle-valve ; =proéle of the same, 
12 = Interior of brachial valve. : 
13 = External cast of brachial valve, slightly concave. 
14 = Exterior of brachial valve, somewhat restored. 
Brachial valve slightly convex for about half the distance 
from the umbo to the curved margin, remainder of valve flat. Umbo 
slightly elevated and marginal. In the interior of the brachial 
valve the most conspicuous feature is a rounded median septum, 
which extends from the hinge-line for rather more than one-third 
of the length of the valve, and lies within the circular depression 
formed by the slightly convex part of the valve. This septum 
thickens slightly at the hinge-line, where it terminates bluntly, and 
in one example it has two short processes at its anterior end (see 
fig. 12). A pair of muscular scars are visible near the posterior 
extremity of the septum. 
Pedicle-valve convex, most elevated at the umbo, height 
about one-third the length of the valve. Umbo smail, marginal,’ 
1 See Hall & Clarke, Pal. N. Y. vol. viii, pt. i (1892) p. 103. 
