266 ME. W. F. KIEBY— A EEVTSION OF 



half their length in front ; abdomen moderately broad, gradually tapering to the 

 extremity, and shorter than the hind wings, the basal segments very slightly thickened, 

 segment 2 with two transverse carinse, segments 3 and 4 with three, and 5 with one, 

 dorsal carina well marked, segment 8 not perfoliate in female : wings rather long and 

 pointed, pterostigma rather short; fore wings with 12-14 antenodal and 7-8 postnodal 

 nervures, the last antenodal and the first two or three postnodal nervures not con- 

 tinuous, cells of the lower postnodal space simple, triangle nearly straight, rather 

 narrow, placed far beyond the plane of that of the hind wings, traversed by one nervure 

 and followed by three rows of cells (or four on one side, as an occasional anomaly), 

 one supratriangular nervure very rarely present, one nervure in the lower basal cell, 

 subtriangular space consisting of three or four cells, nodal sector much waved, sectors 

 of the arculus stalked, the lower sector broken towards the extremity; hind wings 

 broader than the fore wings, with 7-8 antenodal and 8-9 postnodal nervures, the last 

 antenodal continuous, the first two or three postnodals not so, triangle free, followed by 

 three rows of cells, sectors of the triangle united at base, two cross nervures in the lower 

 basal cell : anal appendages rather long. 

 Type Idbellula flavescens, Fabr. 



Genus 3. Hydrobasileus, g. n. 

 (Plate LI. fig. 10.) 



Male. — Allied to Tramea ; abdomen with segments 2-4 transversely carinated : wings 

 long and rather pointed, pterostigma moderate ; fore wings with 16 antenodal and 8 

 postnodal nervures, the last antenodal and first postnodal not continuous, triangle rather 

 long and narrow, oblique, with two cross nervures, and followed by four rows of cells, 

 subtriangular space consisting of five cells, nodal and subnodal sectors much waved, 

 lower sector of the arculus almost continuous ; hind wings twice as broad as the fore 

 wings at the base, and very gradually narrowed towards the tip, with 10-11 antenodal 

 and 9-10 postnodal nervures, the first two postnodals not continuous, triangle free, 

 followed by three and then four rows of cells, sectors of the triangle united at base . 

 anal appendages moderate. 



Type Tramea quaclrivittata, Hag., MS. {Eydrobasileus vittatus, sp. n., postea, 

 p. 314.) 



Genus 4. Camacinia, g. n. 



Head very large ; frontal tubercle bifid ; eyes contiguous in the middle ; abdomen 

 stout, not thickened at the base, the sides nearly parallel, segments 2 and 3 carinated: 

 wings rather long, pointed at the tips, pterostigma moderately long ; front wings with 

 25-27 antenodal and 17-20 postnodal nervures, frequently anastomosing or bifurcating, 

 the three or four first postnodals not continuous, cells of the postnodal area simple, 

 triangle very long and narrow, oblique, on a level with that of the hind wings, reticulated, 



