1 62 A YEAR OF COSTA RICAN NATURAL HISTORY 



stands alone. Most of the trees in these meadows were In 

 the intermediate stage, with the original tree still living. 

 Growing in patches near the water was a striking Urtica- 

 ceous plant {Urera sp.) having stems as thickly set with 

 prickles as they could be placed and large, spiny, deeply in- 

 cised leaves whose upper sides were a very dark, shiny 

 green, the under sides a rich and beautiful purple. 



Walking downstream we came to a small patch of to- 

 bacco with the grower's hut in the middle, went through a 

 cane-brake where the wild cane was several times higher 

 than our heads and finally reached a little back water left 

 by the river in the last flood. Here a few dragonflles (eight 

 species) were flying and were captured. Several times we 

 stopped at some little sandy beaches on the main stream to 

 dredge and were fortunate enough to find six of the curious 

 flattened sand-grubbing larv^ of a Gomphine. 



Some of the back channels of the river contained incred- 

 ible numbers of black tadpoles about an inch long; there 

 were many places a foot wide and two or three yards long 

 that were literally covered with them as thickly as they 

 could be packed, looking like black cloth on the gray-white 

 sand of the bottom. 



Farther upstream, in place of these enchanting meadow 

 strips, the river winds through a stretch of cobblestones 

 and sand, in several channels. Some of these seemed likely 

 places for dragonflies, for the channels contained but little 

 water which flowed much more slowly than that of the main 

 stream. I explored them carefully and minutely, but in 

 vain, although grasshoppers {Heliastus venezuelcz) colored 

 like the sand except for their red hind wings and red tibiae, 

 were present here, A little farther back from the water 

 and five or six feet higher, were patches of tobacco, and be- 

 tween these and the cafetal was a boggy spot which yielded 

 some Insects of several groups. Many small streams cross 



