336 A YEAR OF COSTA RICAN NATURAL HISTORY 



Siquiares at Turrucares in December I found cruentata and 

 capitalis mingled in bright sunshine and moderate shade, 

 taking them both on the very same leaf. A dragonfly with 

 uncolored wings and a very slender bright red body {Heter- 

 agrion erythrogastrum) was fairly common in the dark 

 woods of the Brazil and we had hopes of finding its larva 

 here but in this we were disappointed in spite of prolonged 

 and careful search. 



Between the Brazil and the Ciruelas was a tiny stream 

 emptying into the former and occupying a little "barranca" 

 all of its own, which was narrow, fairly deep and densely 

 vegetated. The plants here were the melastomaceous trees 

 called Marias (Miconia dolichopoda), crotons, the yellow- 

 flowered Maranta called "vijagua" {Calathea insig?iis) 

 and great quantities of caiia brava. It seemed a likely 

 place for dragonflles but they were scarce and few in species. 

 Here and there in the bed of this stream, and at various 

 places on the ground elsewhere in this neighborhood, were 

 black shining patches, due to the presence of grains of me- 

 tallic iron which are attracted by a magnet. 



We usually went to the charming bit of dark wood on the 

 Brazil by following up the Brazil itself from the place where 

 this tiny stream entered It. Where the two streams met 

 was a little swamp, on whose margin was a large wasps' nest 

 attached to the trunk of a tree by one of its long surfaces and 

 in September covering an area perhaps two feet by nine or 

 ten inches. Marks on the trunk showed that the nest had 

 formerly extended at least nine inches farther up for its en- 

 tire width. The entrance to the nest was by a nearly cir- 

 cular opening about an inch in diameter, situated near the 

 top of the nest. The wasps {Synceca azurea) were steel blue 

 in color, with black wings. A., who saw the nest first, came 

 quite close before noticing it and remained quietly looking 

 at it; many more wasps issued through the opening but re- 



