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Show 1902.] DRAGONFLIES OF THE " SKEAT EXPEDITION." 71 very extraordinary development of the armature of the second and third pairs of femurs. This development is paralleled in the American genus Macrothemis and its allies and also in the Old World genera Schizonyx, Neurocena, Zygonyx, and Zygonidia, amongst other Libellidince (see Calvert, Pr. Ac. Philad. 1899, p. 246). Tetrathemis hyalinia has in the male, on each of the second pair of femurs, on their antero-inferior surface, 17 short straight spines directed towards the knee, increasing gradually in size, but the last three longer than the rest, more widely separated and increasing rapidly. On the antero-inferior surface of each of the third pair of femurs is a row of some 20 short curved teeth, their apices directed away from the knee, decreasing gradually in size distally; at the end of the series is a single short straight spine directed towards the knee (see text-fig. 10). Text-fig. 10. 4 < ""•'*•** * Third femur of Tetrathemis hyalinia (X about 10). TETRATHEMIS PULCHRA, sp. n. (Plate Y. fig. 3.) Length of abdomen, <$ 16 mm., $ 15 mm. Length of hind wing, S 17 mm., $ 17'5 mm. Wings hyaline, reticulation black. Fore wings tinged with orange from the base about halfway to the nodus. Hind wings tinged with orange about as far as the nodus. Fore toings. 8-9 (usually 8) antenodals, 5 (in one case on one side 6) postnodals; 1 supra-triangular cross nervule; 2 cross nervules in the lower basal cell. Triangle followed by a single row of cells. Hind wings. 6 or 7 (usually 7) antenodals, 5 postnodals; no supra-triangular cross nervule; 2 cross nervules in lower basal cell. Coloration in the male. Face black with yellow marks as follows : lateral lobes of lower lip, nasus, and rhinarium. The vertex and tubercle are metallic coppery black. Back of head and prothorax black. Thorax black above, a few yellow spots between the wings. Sides citron-yellow with two black bands. The first of these runs from immediately in front of the first pair of wings obliquely downwards to between the second and third pair of femurs. The second runs from immediately in front of the second pair of wmgs down behind the third pair of femurs. The whole ventral surface is black, save that the yellow colour of the flanks extends for a short distance over the ventral surface along either side Ihe legs are black, inner surface of first pair of femurs citron-yellow. Abdomen black, with the following yellow marks:-a spot on either side of segments 1-6, very small on 6, traversed by a black |