161 



REPORT ON A COLLECTION OF DRAGONFLIES FROM THE LAO COUNTRY. 



BY 



Major F. C. Fraser, I. M. S. 

 With a Plate. 



[ The dragonflies here listed were obtained by a native 

 collector during a recent expedition to the north of Siam and 

 adjacent portion of Indo-China, in the region drained by the upper 

 reaches of the Mekong river. The party was badly handicapped for 

 want of a capable and trained man in charge, and this explains the 

 poor results obtained. The following localities are referred to in this 

 paper. 



Utaradit, in central Siam. , 



Nong Nam Pi, Na Kram, Ban Siew, Pak Tah, Chet Ton, on 

 the caravan route between Utaradit and Pak Lai. The road crosses 

 a range of hills, the highest point of which is reached near Chet 

 Ton, about 1800 feet altitude. Pak Lai or Pak Lay is in French 

 Laos, on the Mekong river (Lat 18° 15' N.). 



Ban Pak Tung on the Mekong, N. of Pak Lai. 



Ban Manao, on the Mekong, N. of Saniaburi (Lat. 17o 50' N.). 



Ban Nua, Ban Na An, Ban Na Sao, to the E. of Saniabouri. 

 From Hin Boon, to the south of this town, a caravan road runs N. 

 E. to Vinh on the gulf of Tonkin. The route crosses a range of 

 hills, and at its highest point is about 1,000 feet above sea level. 

 The country there is described as " high mountains, no jungle, but 

 rocks and tall grass." Eds.]. 



The collection consists of 165 specimens and is only poorly 

 representative of the rich Odonate fauna of the region visited. As proof 

 of this, I need only mention that there is not a single species present 

 of the large subfamily Gomphiwae, and there are only 6 representa- 

 tives of the whole of the suborder Zygoptera which form fully 50 

 per cent of the Odonate fauna of the region. It is obvious that the 

 native collector passed over the smaller species as unworthy of 

 collecting (there are only 2 specimens of Coenagrioninae), and for 

 the rest he took those most calculated to attract his attention 

 by reason of their striking colours or size. The Corduliinae, 



VOL. IV, NO. 3, 1921. 



