46 BULLETIN 647, TJ. S. DEPARTMENT OF AGRICULTURE. 
ants are dead. Thus about 94 per cent of the mealybugs taken from 
the ants were dead or discolored and scarcely able to move, while 
with the black scales and aphids carried the percentage of dead was 
still higher. On the other hand, of those insects which do not fur- 
nish honeydew to the ants most are alive when taken from their 
captors. Nearly all captive white flies are alive, as are the psocids, 
and even such fragile insects as thrips may be handled so lightly by 
their captors as to remain apparently uninjured. Thus, on one 
occasion, a thrips dropped by an ant at once started to run, when 
another ant seized and bit it viciously several times, after which the 
only sign of life was a twitching of legs and antennae. 
The ants almost always carry their scale and aphid hosts, as well 
as all other captured insects, to the nest, which is rarely if ever so 
situated as to afford living conditions to these insects. On rare occa- 
sions, in Louisiana, living mealybugs had been found in ant trap- 
nests, containing only dried straw and manure, but this happened in 
winter, when the mealybugs left not only the trees where there were 
ants, but also those in a part of the orchard where no ants occurred, 
and located on Bermuda grass. The soft scales found in ants' nests 
almost always have been dead. On one occasion when an exception- 
ally large number of ants carrying mealybugs down an orange tree 
could be traced to the nest in the rotting wood, many dead and dis- 
colored mealybugs and mealybug particles were found and 80 whole 
bugs counted. There were only 2 living mealybugs, and these ap- 
peared to be diseased, being unable to move except for twitching the 
legs a little. 
The ants carry their host insects in considerable number only when 
these insects are exceptionally numerous, at which times they are 
able to supply a great deal more honeydew than the ants actually 
require. In Louisiana the ant attendance on the black scale and the 
citrus mealybug was nearly always in greater number than could 
obtain honeydew from them continuously. In California, however, 
the black scale, where unchecked by fumigation, becomes very numer- 
ous, overflowing the trees and covering them with sooty mold. On 
such trees the ants earn 7 many scales at times. Thus in one orchard, 
in which both ants and black scales occurred in exceptionally large 
numbers, an unusually large number of ants were so engaged. For- 
tunately for observation, many of the nests to which ants could be 
traced were in the rotting stubs of cut branches. In these nests the 
scale phase most readily seen (that is, shells of mature scales) was 
scattered throughout the ants r galleries. Many nests, with their 
contents, were removed and examined, and the remains of numerous 
insects found there, but the black scales, of which there were 118 
young stages, all dead, and 97 shells of mature scales, outnumbered 
