The Odonata or Drari,„ijfies of South Africa. 339 



Coloured wings are exceedingly rare in this subfamily. 



Almost as uniform as the colour system is the ueuration in its 

 principal features and even down to rather minute details ; neverthe- 

 less a careful investigation (initiated chiefly by Mr. E. B. Williamson) 

 has brought forth a numlier of jiretty coustant and systema'ically 

 valuable differences. To the uniformity in colour and ueuration the 

 great and conspicuous variety in the male terminal appendages is in 

 strong contrast. It is natural that these differences, which form an 

 attractive object of study, should have guided the first monographers 

 in their descriptions, and, unfortunately, also in their attempts at a 

 systematic arrangement. Great difficulties arise from this latter 

 point lief ore the student, especially where females alone are at hand. 

 A new disposition of the subfamily, based, not on unisexual characters, 

 but chiefly on ueuration, as a bisexual as well as phylogeuetically 

 important character, is a need of the time, and the chief lines of such 

 a disposition are drawn by Mr. Williamson for a limited geographical 

 (Oriental) group. This disposition will be followed here as well as in 

 other publications of the writer. 



Uniform as their colour pattern is also the manner of life of 

 Gomphinae (and both uniformities may well he esteemed inter- 

 dependent). Their flight is exceedingly swift but not lasting ; they 

 mostly stay ou the ground, or very close to the ground on low 

 vegetation, rarely ascending to some height in bushes ; from their 

 resting-place they take swift flights, darting upon some prey, or 

 upon an intruder of their own or an allied kind, and then return with 

 equal rapidity to their starting-jwint or alight not far from the same. 

 Most of them are very wary insects, and this quality, together with the 

 highly cryptic character of their pattern in natural haunts, answers for 

 the fact that many Gomjihiiiae are very rare in collections, many 

 described from single specimens, and many still to be discovered in 

 the less worked districts of the globe. Perhaps there are more species 

 of limited range in Gomiihinae than in most other groups of Odonata, 

 though wide ranging forms are liy no means absent. Where they are 

 better known most species have been ascertained to inhabit running 

 waters, from very slow to quite swift kinds. A few only are known 

 to live in still waters, but the larger number where there is motion in 

 the water, and very few are inhabitants of small jionds and swamps 

 which abound in many other kinds of dragonflies. 



'Plate XII, fig. 3, gives an idea of the larvae of the more typiical 

 groups; the fiat body, short labium, elongate and flattened third 

 joint of antennae, fossorial structure of the hard and villose legs are 

 the characteristic external features of the Gomphus nymph. But the 



