2 INTRODUCTION [CH. 



phylogenetic grounds, raises them to the rank, of a Sub-Class 

 (Libelluloidea). This seems to be going rather too far, particularly 

 now that the very important character of the radial sector has 

 been shewn to hold only for the Anisoptera, and not for the 

 Zygoptera. We shall therefore be content to treat the Dragon- 

 flies as a very distinct and isolated Order of Insects, under the 

 name Odonata or Paraneuroptera. 



Little attention was paid to the Odonata during the first half 

 of the nineteenth century, and the total of described species 

 remained small, despite the excellent work of Rambur [127] and 

 others. The darkness was dispelled by the appearance on the 

 scene of the great Belgian master, rightly called the "Father of 

 Odonatology," Baron Edmond de Selys-Longchamps. His work 

 on the Order began just before the middle of the century, and 

 lasted until his death in 1890. His whole life was devoted to the 

 study of Natural History. But the Dragonflies soon became his 

 favourite group, and remained so to the end. He not only built 

 up a magnificent collection of these insects, but published mono- 

 graphs of every subfamily except the Libellulinae. His collections, 

 which contain an enormous number of types, were placed at his 

 death in the Natural History Museum at Brussels, where, we most 

 sincerely trust, they have remained untouched by the greedy 

 hands of the Despoilers. 



The life of de Selys marks the Classical Period of the study of 

 Odonata. It was he who first saw the importance of the wing- 

 venation as the basis of classification, and who started the study 

 of the Order along the right lines. To him we owe the facts that 

 the Odonata now stand as one of the best-understood of all Orders 

 of Insects, and that their classification is based on a natural 

 system supported by an ever-increasing weight of morphological 

 and phylogenetic evidence. 



After his death, the work of de Selys was continued by his 

 sons, who arranged for the publication of a series of catalogues 

 of the various groups of animals in their father's collection. These 

 catalogues became expanded into complete and magnificent mono- 

 graphs, dealing with every known species. In the case of the 

 Odonata, the Corduliinae, Aeschninae and Calopterygidae were en- 

 trusted to M. Rene Martin of Paris. He has faithfully completed 



