1902.] DRAGONFLIES OF THE " SKEAT EXPEDITIOX." 71 



very extraordinaiy development of the armature of the second 

 and third pairs of femurs. This development is paralleled in the 

 American genias Macrothemis and its allies and also in the Old 

 World genera Schizonyx, Neurocena, Zygonyx, and Zygonidia, 

 amongst other Libellulince (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 sejjarated and 

 increasing rapidly. On the antero- inferior surface of each of the 

 third pair of femurs is a row of some 20 short cui'ved 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. 



Third femur of Tetrathemis hyalinia (X about IQ). 



Tetrathemis pui-chra, sp. n. (Plate V. fig. 3.) 



Length of abdomen, c? 16 mm., $ 15 mm. Length of hind 

 wing, (^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 citi'on-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 wings 

 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 The 

 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 



