26 Unhersity of Michigan 



pointing for collecting. In seven days we failed to add a 

 single additional species to our dragonfly list, and in this well- 

 watered region we found only two species of Hetaerinas. 

 Collected March 15-21, 1920. 



Hetaerina caja was the only species which we found on 

 the main streams. On the Yumarito both caja and macropus 

 occurred. Caja, which was wanting at Aroa, ten or fifteen 

 miles away, was the commoner Hetaerina at Boqueron. At 

 Palma Sola, below Boqueron, and where the streams were 

 slower, caja was still more abundant relatively, macropus being 

 represented in our collections by only two females collected 

 there. At Caserio Silva, where the same two species, and 

 these two only, were found, among rockier conditions, caja 

 was rare and macropus was abundant. 



9. Caserio Silva. A posada between Valencia and Bejuma, 

 about seven miles out of Bejuma, Venezuela. Situated on a 

 small, clear stream six to ten feet wide, the Rio La Mona, 

 which is generally in the sun, but has a little native forest 

 remaining on it. It is generally swift-flowing in a gravelly 

 bed, with pools and ripples, but no waterfalls. Near Caserio 

 Silva it flows into the Rio Chirgua, a stream in a deep, pre- 

 cipitous valley, of which the native flora has been largely 

 destroyed. The Rio Chirgua is twenty to thirty feet wide 

 and has pools six feet deep in it. The bed is rocky or grav- 

 elly. Its waters eventually reach the Orinoco. Elevation not 

 known, but probably about 1,500 to 2,000 feet. Collected 

 February 20-23, 1920. 



As was to be expected from the generally swift character 

 of the streams, caja was rare here and was taken only on 

 the Chirgua. Macropus was much more abundant, occurring 

 both on the Chirgua and La Mona. Our failure to get capi- 



