. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. 218 Prof. T. R. Jones and Dr. H. B. Holl on the surface of the valves is seen in Cythere [/EchminaT] umbo- nata7 Williamson, from the Chalk (Monograph Cretac. Entom. Pal. Soc. 1848, pi. 2. fig. 3), in which the sharp boss is some- what variable in its position, though mainly affecting the postero-ventral region. 1. JEchnina cuspidata, n. sp. PI. XIV. fig. 8, and woodcut, fig. 2. Carapace-valve suboblong, convex and produced at the middle (towards the postero- dorsal region) in
. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. 218 Prof. T. R. Jones and Dr. H. B. Holl on the surface of the valves is seen in Cythere [/EchminaT] umbo- nata7 Williamson, from the Chalk (Monograph Cretac. Entom. Pal. Soc. 1848, pi. 2. fig. 3), in which the sharp boss is some- what variable in its position, though mainly affecting the postero-ventral region. 1. JEchnina cuspidata, n. sp. PI. XIV. fig. 8, and woodcut, fig. 2. Carapace-valve suboblong, convex and produced at the middle (towards the postero- dorsal region) into a stout sharp spike; dorsal edge straight, ventral edge ellipti- Fig. 2. JI£ehmina cuspidata. cal; one end more broadly Right valve: the spine is broken, rounded than the other. (Magnified about 20 diameters.) We have here evidently a very close approximation to Pro- fessor James Hall's Cytherina {JEchmina\ spinosa (Palseont. New York, vol. ii. p. 317, pi. 67. figs. 17-21), from the Niagara Shale at Lockport, in the State of New York; but the latter is more quadrate in outline and somewhat depressed at the root of the spine, which, though nearly central, is near the dorsal margin. The fragment figured obliquely in PI. XIV. fig. 8, and more definitely shown in the woodcut, fig. 2, is from the Wen- lock Limestone of Croft's Quarry, near West Malvern. 2. JEchmina clavulus, sp. nov. Woodcut, fig. 3. This is smaller and relatively shorter than the foregoing, and has nearly all the surface of the valve taken up with the root of the great spike or spine, which is proportionally larger than that in 2E. cuspidata. \ / Found in the Wenlock Lime- / /' stone, with the last men- p-lg. 3. JEchmina davulus. tioned. Both valves, one of them restored. (Magnified about 20 diameters.) BeyricJiia intermedia, sp. nov. PI. XV. fig. 7. Carapace-valve small, convex, suborbicular (length to height as 4 to 3|); ventral edge semicircular, ends boldly curved, one rather less so than the other; dorsal
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