THE OSTRACODOUS GENUS BATRDIA. 577 
This Carboniferous specimen is relatively higher and has the dorsal 
border more angulate than Permian examples. It may be described 
as follows :— 
Elongately subpentagonal ; convex : length twice the height, which 
is greatest at the anterior third, from which point the dorsal border 
descends in right lines towards each extremity. Anterior extremity 
broad, truncated inwards; ventral border projecting (flap-like) at 
the anterior ventral angle, and sloping inwards behind towards the 
posterior extremity: this end of the valves is bluntly rostrated, 
the upper slope being deep and abrupt. Lateral contour lenticular ; 
greatest width about the anterior third, and more than one third of 
the length. Surface smooth. Length ;4 inch. 
B. amputata is a strongly characterized species. It can always 
be distinguished by the angularity of its general outline and its 
abruptly truncate anterior end. 
As a Carboniferous species, it has only occurred in the Lower Car- 
boniferous-Limestone shale of Paiston Quarry, East Lothian, where 
it was found by the officers of the Geological Survey of Scotland. 
13. Barrpra prmcrsa,n.sp. Plate XXXII. figs. 1-6. 
Ovately subrhomboidal, compressed; length less than twice the 
height. Dorsal border strongly convex, with the posterior slope 
much the deepest; the anterior slope forms an abrupt angle with 
the anterior extremity, which is broad and obliquely truncate in- 
wards and downwards ; ventral border straight ; posterior extremity 
rounded or slightly subangular. The left valve overlaps the right 
along the whole of its border, most strongly so dorsally and at the 
antero-dorsal angle. Lateral contour more or less wedge-shaped, 
the Ee width being at the anterior third. Surface smooth ? 
Length 4, inch. 
The specimens on which the preceding description is based were 
found in a thin limestone of the Calciferous-Sandstone series near 
Randerstone, Fife. Their outline somewhat resembles a reversed 
Leperditia; their mode of hingement, however, their truncated 
anterior end, and wedge-like lateral contour show that such like- 
ness is not real. 
This species has been met with only at the above-mentioned locality. 
14, Barepra nitmpa,n.sp. Plate XXXII. figs. 9-12. 
Elongately subovate; highest at the anterior third; rounded in 
front, tapering to a point behind ; very convex: length. two and a 
half times the height; width ereater than the height, - The dorsal 
border slopes gently downwards from the anterior to beyond the 
posterior third, whence it descends abruptly to form the posterior 
extremity; the ventral border is conyex. Overlap of the left valve 
moderate. Lateral poukaun tumidly lenticular, widest in the centre. 
Surface smooth. Length 5), inch. 
This neat and plump form of carapace has apparently no very 
near Carboniferous relations. Perhaps it approaches most closely to 
the mucronate forms of the genus. 
The only example which we have found occurred at Anstruther, 
