370 Records of the Indian Museum. [Vol. XXIV, 



limited extent as regards his series Gomphus, which remains still 

 in an unsatisfactory state for the systematist. The characters I 

 have given in my generic definitions are such as I hope will render 

 the reference of species to their appropriate genera not a very 

 difficult task. I confess I have myself not found it easy in many 

 cases. 



As to terms employed, it is perhaps necessary to explain that 

 as regards the colour pattern of the synthorax an imaginary typical 

 species would have the dorsum (mesepisternites) black with a 

 ' dorsal 1 yellow stripe or band on either side of the median suture 

 (or mid-dorsal carina) and external to this a juxta-humeral (or more 

 shortly humeral) stripe just internal to the humeral suture. The 

 sides of the synthorax of such a species would be yellow, with a 

 fine black line marking the position of the two lateral sutures. The 

 term meso-thoracic collar explains itself. De Selys uses also the 

 term antehumeral in the same sense as I give here to the word 

 dorsal, referring to the yellow bands placed near the mid-dorsal 

 carina. 



For tertns used iix discussing venation I would refer the reader 

 to Tillyard's book " The Biology of Dragonflies" or to Needham's 

 " Genealogic study of Dragonfly wing-venation" ' or to William- 

 son's paper already quoted on ' The Dragonflies of Burma and 

 Lower Siam.' For wing-photographs I am indebted, as on other 

 occasions, to Mr. F. W. Campion. 



I fear that this paper is in danger of being too lengthy already. 

 I will therefore not attempt to deal with the interesting questions 

 of geographical distribution that suggest themselves. They may 

 be postponed for future consideration, when our knowledge of the 

 group is more complete. 



I have not been able to deal with certain questions of synony- 

 my satisfactorily, especially as concerns some of the species of 

 Ictinus. I hope they will be tackled and solved b3' field-workers 

 in India. 



In the following list species marked with an asterisk have 

 not been seen by me. Species of doubtful distinctness are put 

 in brackets. I have throughout adopted the synonymy of Kirby's 

 ' Catalogue.' 



Series Hagenius. 



Sieboldius japponicus Selys. 



Series Diastatomma. 



Ictinus rapax Ramb. 

 ,, (praecox)* Selys. 

 ,, (mordax)* Selys. 

 ,, angulosus Selys. 

 ,, (atrox)* Selys. 

 Gomphidia T-nigrum Selys. 



i Proc. U.S. Nat. Mits. XXVI. pp. 703-764 (1903). 



