. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. the Palaeozoic Bwaived Entomostraca. 219 into the depressed area along the straight edge, thus forming- three unequal lobes on the dorsal region, the rest of the valve's surface remaining smoothly convex, bordered by a narrow depressed rim. The shape of the valve is that common among Primitice; but, though the sulci are too short for those usually charac- teristic of Beyrichice (excepting B. Wilckensiana, Jones, Ann. Nat. Hist. ser. 2. vol. xvi. pi. 5. figs. 17 & 18), yet
. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. the Palaeozoic Bwaived Entomostraca. 219 into the depressed area along the straight edge, thus forming- three unequal lobes on the dorsal region, the rest of the valve's surface remaining smoothly convex, bordered by a narrow depressed rim. The shape of the valve is that common among Primitice; but, though the sulci are too short for those usually charac- teristic of Beyrichice (excepting B. Wilckensiana, Jones, Ann. Nat. Hist. ser. 2. vol. xvi. pi. 5. figs. 17 & 18), yet we are unwilling to admit a bisulcate form among the " Primitive" until further evidence proves the necessity of breaking down the provisional limitation of that genus. In the meantime we regard the pretty little specimen before us as an intermediate form, as its name intimates. Our figured specimen is from the Aymestry Limestone of Chance's Pitch, Malvern, where specimens are not uncommon ; and some few casts of apparently the same species occur inWool- hope Shale from near Malvern, in Dr. Grindrod's collection. 1. Primitia lenticular is, sp. nov. Woodcut, fig. 4 a, b, c. Carapace smooth or slightly rugose (perhaps from weather- ing), convex, nearly ovate; elliptically rounded below, decidedly arched above, unequally rounded at the ends; the larger (pos- terior) extremity with a marginal rim and compressed; ventral border slightly lipped. Dorsal aspect elongate-ovate, rather compressed in front of the centre, and acute posteriorly. End view subacute-oval. This is near to P. ovata,;H. Ann. Nat. Hist. ser. 3. vol. xvi. p. 423, pi. 13. fig. 13, and P. obsoleta, J. & H. he. eit. fig. 12, both Scandinavian. It is shorter, however, more convex, and more ovate (being higher as 32 : 30, and shorter as 43 : 45) than the former, and it has a posterior marginal rim, with very little of it continued on to the ventral border; it has also a different edge view, being les
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