228 A YEAR OF COSTA RICAN NATURAL HISTORY 



shade. Here came the fairy humming-birds to bathe, flying 

 through the water repeatedly at our very feet and after each 

 dip perching on a branch not a yard away to shake their 

 glittering feathers. Here, too, we often found two species 

 of dragonflies whose habit it is to live along just such deeply 

 shaded streams, Heteragrion erythrogastrum, whose male has 

 a bright red body 45 mm. long and Protoneura remissa with 

 a thread-like body 34 mm. long. In the latter the only 

 visible parts are its red eyes and a small blue spot near its 

 hind end. 



In this part of the forest and at various points along the 

 Reventazon road, we saw, at difi"erent times, three species 

 of an extraordinary group of dragonflies, the Anormostig- 

 matini, confined to tropical America. They are recogniz- 

 able by the great length (two to five inches) and extreme 

 slenderness of the abdomen, by the front and hind wings 

 being long, narrow and of equal size and by the stigma (or 

 colored spot on the front edge of each wing near its tip) 

 being divided by cross-veins into several minute areas or 

 "cells," instead of constituting but one cell as in the great 

 majority of dragonflies. The largest of these three species 

 was Megaloprepus ccerulatus, described in Chapter XV. It is 

 chiefly an inhabitant of the lower country, and an individual 

 observed on September 29 near the upper end of this road 

 at about 3000 feet, had reached the highest elevation in 

 Costa Rica at which we ever saw this species. The second 

 in order of size was Mecistogaster ornatus, whose body length 

 was 3 to 4 inches (75-100 mm.) and wing expanse 3^5 

 to 4'*/5 inches (90 to 120 mm.). Each wing-tip inward for 

 5 to 8 mm. was greenish-yellow, bright yellow or orange. 

 Its area of distribution is from Vera Cruz and Durango 

 States, Mexico, to the Amazon valley. The third species 

 was Mecistogaster modestus with a body 3 inches in length 

 and a wing-spread of 3^5 to 3V5 inches. The wings were 



