106 
NATURE S CRAFTSMEN 
will be amazed to find them everywhere, not only 
on the oaks and rose-bushes, but on the maples 
and lindens of our lawns, on the hickories and 
willows of our woods and hedges, on the golden- 
rod of the fields, and indeed on very many of the 
plants all about us. The galls of the golden- 
rod, however, are produced by a Tineid moth; 
and most of those on other low plants and shrubs 
are the work of lice, mites and beetles. True 
galls, that is those made by the gall-flies, differ 
from each other vastly more than do the species 
of little craftsmen that dwell in them. But 
whether burr, berry, wart, cone, ‘ gouty,’ or ap¬ 
ple be their shape, all are inhabited. The same 
kind of fly will produce different kinds of galls 
on different kinds of plants; likewise, too, dif¬ 
ferent kinds of flies will produce different kinds 
of galls on the same plant. Always, however, 
each species of gall-fly infests a particular part 
of the plant, such as the root, leaf or stem, and 
that part alone; and its galls are always as near 
alike as two peas. On seeing a gall, then, we can 
be practically sure what little craftsman started 
the house building. But, if we hatch and rear the 
little grub that is installed therein, we are not 
always sure to get a specimen similar to the one 
we are expecting. And why? Because the same 
trick of fate which works changelings in other 
cradles is frequently effected here. Ofttimes the 
