2 Psyche [February 



the tree's buttresses. The colony was apparently about to swarm, 

 as the air about the nest was full of bees flying back and forth in 

 zig-zag paths like those described by some dancing Empidid flies. 

 A compact mass of the insects had settled to one side of the entrance 

 spout. On putting my tweezers into this mass I was at once 

 enveloped in a cloud of loudly humming bees, which, however, did 

 not settle on my body but kept darting against my face and hands, 

 often falling over on their backs onto the ground or onto my 

 clothing. They moved very rapidly and as if intoxicated. At 

 the same time they emitted a distinct rancid-butter odor, like that 

 of the ants of the genera Tapinoma and Azteca. On my moving 

 away to a distance of about 40 feet, they all left me quite suddenly 

 and returned to their nest. 



According to Silvestri, this species may also bite, but its mandi- 

 bles are feeble and innocuous. Von Ihering describes it as a 

 "very wild" bee and as often visiting carrion, cow-dung or other 

 excrement. He gives its native Brazilian name as "sanharo." 



Trigona nigerrima Cresson. 



A few specimens of this, the largest species seen, were taken on 

 flowers in the banana plantations at Quirigua, Guatemala. 



Trigona jaty F. Smith. 



This small, slender, honey-yellow species is common in western 

 Guatemala, at Escuintla and Patulul, nesting in crevices between 

 the buttresses or bark-ridges of large trees and between the clap- 

 boards of houses. In the latter situations it seems to prefer the 

 corners where the clap-boards abut on the door and window frames. 

 The nest entrance is a spout, sometimes fully an inch long but only 

 about the diameter of a lead-pencil, either cylindrical or somewhat 

 flattened and occasionally twisted. The wax of which this spout 

 consists is pale yellow and as thin as paper, so that it collapses 

 when rudely touched, especially when the temperature is high. 

 In the early morning the bees are often seen flying in a small com- 

 pact swarm just in front of the entrance, all with dangling legs and 

 with their faces turned towards the opening. They are extremely 

 timid and when disturbed at once retreat into the opening and 

 cannot be induced, by poking straws, etc. into it, to come out and 

 defend their nest. The natives of Guatemala call these little bees 



