. Fossil plants : for students of botany and geology . Paleobotany. XXVIlJ ALETHOPTERIS 573 obtained by Lyell ^ from the Coal-Measures of Nova Scotia, in the smaller size of the meshes. Linopteris obliqua occurs in the Upper and Middle Coal-Measures of Britain; it is recorded by Zeiller from Asia Minor, by Lesquereux^ from Pennsylvania, and by other authors from several European localities. The pinnules frequently occur detached from the frond and like those of some species of Neuropteris were caducous. Linopteris is rare in British Fig. 374. Linopteris neuropteroides,G\x\h. (Pinnule
. Fossil plants : for students of botany and geology . Paleobotany. XXVIlJ ALETHOPTERIS 573 obtained by Lyell ^ from the Coal-Measures of Nova Scotia, in the smaller size of the meshes. Linopteris obliqua occurs in the Upper and Middle Coal-Measures of Britain; it is recorded by Zeiller from Asia Minor, by Lesquereux^ from Pennsylvania, and by other authors from several European localities. The pinnules frequently occur detached from the frond and like those of some species of Neuropteris were caducous. Linopteris is rare in British Fig. 374. Linopteris neuropteroides,G\x\h. (Pinnule of type-specimen. Enlarged. After Zeiller.) Alethopteris. The name Alethopteris, instituted by Sternberg*, is applied to compound fronds often reaching a considerable size, exhibiting the following features: The linear pinnules are attached by the whole breadth of the base, with the lower edge of the lamina decurrent and usually continuous with that of the next pinnule (figs. 290, A, p. 399; 375). The ultimate segments- are entire, with an acute or rounded apex and often characterised by a fairly thick lamina convex on the upper surface. From a prominent midrib, continued to the apex of the pinnule, numerous simple and forked secondary veins are given oflF at a wide angle, the decurrent portion of the lamina being supplied by veins direct from the axis of the pinna. _ In the upper part of a frond or primary pinna the pinnules may be replaced by a continuous, lobed, or entire simple lamina. The main rachis occasionally exhibits dichotomous branching, but the fronds are for the most part constructed on the pinnate plan. Single Cyclopteroid pinnules* occur on the petiole of some species of the genus. 1 LyeU (45) A. Vol. ii. p. 202. " Lesquereux (80) A. p. 146. 3 Sternberg (26) A. * Grand'Bury (04).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may n
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