THE OSTRACODOUS GENUS BAIRDIA. 573 
We have specimens from Whorlton and from various localities in 
Scotland that possess some affinity to B. mucronata, but which differ 
from it in having an elliptical ventral margin, a more symmetrical 
and less pointed posterior extremity, and a lateral contour which, 
though convex, is flattened over its central portion. Some of the 
specimens show a tendency to become subrhomboidal, with a faintly 
rostrated posterior extremity, and so approach B. plebera. But we 
are inclined to look upon these specimens as distinct both from the 
latter species and B. mucronata, and describe them as follows :— 
Subpyriform or subrhomboidal in outline; greatest height about 
the anterior third; length about two and a half times the height, 
or less. Both dorsal and ventral borders convex. Anterior ex- 
tremity roundly prominent; posterior extremity rather acutely 
pointed. Lateral contour flatly convex, with the posterior end the 
most acute. Surface smooth. Length j; inch. 
Localities of B. submucronata. 
In England and Wales. In Yoredale Rocks at Whorlton, Dur- 
ham; and in Carboniferous Limestone at Great Ormes Head, 
Caernarvonshire. 
In Scotland. Carboniferous Limestone (Upper): Gare (Carluke) 
and Robroystone in Lanarkshire; Orchard, near Pollokshaws, in 
Renfrewshire. 
Carboniferous Limestone (Lower): Currielee Limeworks, Maga- 
zine Limeworks, Mansfield, in Edinburghshire; Corrieburn, Crai- 
genglen (Campsie), and Sculliongeur, in Stirlingshire ; Carluke and 
Brockley in Lanarkshire. 
Lower Carboniferous Series: Bonshawburnhead Quarry, Dum- 
friesshire. 
8. BarrpIA SUBELONGATA, n. sp. Plate XXX. figs. 1-11 & 16. 
B. subcylindrica (Minster), Jones & Kirkby, 1867, Trans. Geol. 
Soc. Glasgow, vol. i. p. 221. 
B. subcylindrica (Minster), Armstrong & Young’s Catalogue of 
Carb. Foss. of Western Scotland (1871). 
We have many specimens of a long, narrow form of Bairdia, 
which have much in common with B. elongata, Munster, but do not 
approach near enough to that species (so far as we know it) to 
permit of absolute identification. This form we describe under the 
name of subelongata. 
Elongate; length more than three times the height. Dorsal 
border straight or very slightly convex ; ventral border straight or 
very slightly concave, and parallel (or nearly so) with the dorsal 
border. Anterior extremity broadly rounded, evenly so in many 
cases, but sometimes most prominent above; posterior extremity 
bluntly pointed, being diagonally truncate; it were, above and 
below. Dorsal overlap moderate. Lateral ion about four times 
as long as wide, flat or flatly convex for a goal central third, with 
pointed ends, the anterior being rather the most acute. Surface 
smooth. Length ;/; inch. 
Q.J.G.8. No. 140. ee 2R 
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