. Contributions to Canadian palæontology. Paleontology. 118 CONTRIBUTION'S TO CANADIAN PALEONTOLOGY strongly-curved anterior margin, and a still more arched posterior border. Their breadth and length are in the ratio of 1:2-3. The. Fig. 25.—Penthetria transitoria, Handlirsch. radius is nearly straight, and reaches more than seven-tenths the length of the wing. The sector arises immediately below the first fourth of the length of the wing, is gently arcuate, and just distal to half its own length sends off an oblique indistinct anterior branch toward the end of the radiuis. The radiomedial cros
. Contributions to Canadian palæontology. Paleontology. 118 CONTRIBUTION'S TO CANADIAN PALEONTOLOGY strongly-curved anterior margin, and a still more arched posterior border. Their breadth and length are in the ratio of 1:2-3. The. Fig. 25.—Penthetria transitoria, Handlirsch. radius is nearly straight, and reaches more than seven-tenths the length of the wing. The sector arises immediately below the first fourth of the length of the wing, is gently arcuate, and just distal to half its own length sends off an oblique indistinct anterior branch toward the end of the radiuis. The radiomedial cross-vein lies in the centre of the wing, and nearly twice as far from the origin as from the bifurcation of the sector. Quite a distance below the middle of the wing, the media separates into two strongly divergent branches. The cubitus is relatively gently curved, and with its posterior branch reaches the middle of the posterior margin. Behind it may be seen a distinct divergent fold and an equally divergent anal vein. The mediocubital vein is isituaited twice as far above the radiomedial vein as is the latter above the furcation of the media. In the costal region the wing was very opaque. Penthetria canadensis, sp. nov. Kg. 26. Locality: Tulameen river, opposite Vermilion cliff—(August 6, 1906. ). This form consists of two wings pertaining to one individual. The wings are 10™™ long, with slightly arched anterior border, and strongly curved posterior margin. The breadth 'and the length are in the proportion of 1:2-2. The radius curves gently toward the anterior margin, and extends seven-tenths the length of the wing. Its sector springs forth just below the first fourth of the length of the wing, and separates into two branches directly above half its own length; the anterior of these is strongly and simply curved, is widely divergent, 'and strikes the margin decidedly nearer to the radius than to the posterior branch. The latter is strongly curved. The radio- medi
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectpaleontology, bookyea
