lo University of Micluyan 



Fria are located. At Cristalina, in the Magdalena basin, all 

 four species, caja, macropiis, capitalis and miniata, occur. 

 Why should miniata have stopped at the Catatumbo when the 

 apparently more specialized caja ranges far to the east and 

 west ? 



Another genus of dragonflies which is as closely confined 

 to streams as Hetaerina is Heteragrion. In the San Esteban 

 and Yaracuy valleys and over the mountains from them in 

 the Orinoco drainage occurs Heteragrion chrysops alone. In 

 the Magdalena basin, far to the west, occurs Heteragrion 

 mitrattim and three other species, but not chrysops. But in 

 the Catatumbo basin chrysops and mitratum both occur. If 

 chrysops could come as far west as the Catatumbo and mitra- 

 ttim could come as far east, and both find a congenial habitat 

 there, why has not mitratum extended its range to the east, 

 over the path chrysops has come ; and why has not chrysops 

 ranged westward to the Magdalena by the same route uiitra- 

 tum has travelled? 



Species and Locauties 



In a former paper (Misc. Pub., Mus. Zool.. L'niv. of 

 Mich., Xo. 9) I have listed the several collecting trips to 

 the American tropics in which I have had a part or from 

 which I have obtained the dragonflies for study. This paper 

 deals with the Hetaerinas, numbering over 3,500 specimens, 

 which have been taken on these trips. The Guatemalan Hetae- 

 rinas, collected in 1905, have been fully dealt with by Dr. 

 Calvert in the B. C. A., and they arc not again referred to 

 in this paper. The records from a single stream in Honduras, 

 collected the same year and already incorporated in the B. C. 

 A., are, however, again listed for purposes of comparison. The 

 large lot of material on which this paper is based has been 



