166 The Naturalist in La Plata. 
wanted, and spitefully made up its mind to stay 
where it was. The leaf-cutter then gave up the 
contest. Suddenly rising up into the air, it hovered, 
hawk-like, above the Monedula for a moment, then 
pounced down on its back, and clung there, 
furiously biting, until its animosity was thoroughly 
appeased; then it flew off, leaving the other 
master of the field certainly, but greatly discom- 
posed, and perhaps seriously injured about the 
base of the wings. I was rather surprised that 
they were not cut quite off, for a leaf-cutting bee 
can use its teeth as deftly as a tailor can his 
shears. 
Doubtless to bees, as to men, revenge is sweeter 
than honey. But, in the face of mental science, 
can a creature as low down in the scale of organiza- 
tion as a leaf-cutting bee be credited with anything 
so intelligent and emotional as deliberate anger and 
revenge, ‘which implies the need of retaliation to 
satisfy the feelings of the person (or bee) offended ?”’ 
According to Bain (Mental and Moral Science) only 
the highest animals—stags and bulls he mentions— 
can be credited with the developed form of anger, 
which he describes as an excitement caused by pain, 
reaching the centres of activity, and containing an 
impulse knowinely to inflict suffermg on another 
sentient being. Here, if man only is meant, the 
spark is perhaps accounted for, but not the barrel 
of gunpowder. ‘The explosive material is, however, 
found in the breast of nearly every living creature. 
The bull—ranking high according to Bain, though 
I myself should place him nearly on a level mentally 
