39 
balls, which their runners were in the habit of kicking before them as 
they journeyed from one point to another. There are other species of the 
same genus inhabiting North America, notably 7. mexicana Comstock, 
T. gemmifera, T. pustulata, T. fulgens, and T. cornuta Cockerell. None 
of these, however, occur in the same abundance as 7. larrew, and 
therefore do not offer the same possible commercial interests. 
The third substance of commercial importance derived from scale 
insects is a pure white wax, which is secreted by the Chinese and 
Japanese Hricerus pé-la and by the Indian Ceroplastes ceriferus. On 
account of its expense, and on account of more or less available sub- 
stitutes, this wax has not become of great commercial importance in 
Europe, but is much used in the Eastern countries, both in the making 
of wax candles and in medicine. The Chinese wax is said to have ten 
times the illuminating power of other waxes. It is a beautiful wax, 
resembling beeswax in its chemical composition more nearly than the 
vegetable waxes, and is clear white in color. We have in this country, 
as well as in other parts of the world, species congeneric with the Indian 
wax insect, and a very common form in the South, occurring abundantly 
on the gall berry, is the Ceroplastes floridensis Comst. The amount of 
waxy secretion of this species is not so abundant as in the Indian 
species. 
In the far Southwest, however, there is a wax insect which apparently 
needs very greatly careful investigation from the commercial stand- 
point. This insect is Cerococcus quercus, described by Comstock in the 
Annual Report of the Department of Agriculture for. 1881-82, from 
several specimens found upon twigs of oak in the old collection of the 
Department of Agriculture, and which came originally from Arizona. 
Professor Comstock also saw specimens in the Museum of Comparative 
Zoology at Cambridge, which were collected in California by Osten 
Sacken. Three species of oak are recorded by Comstock as offering 
food for this insect, viZ, @uercus oblongifolia, Q. undulata variety 
wrightii, and Q. agrifolia. “Judging from the specimens before me,” 
said Comstock, “this insect occurs in sufficiently great numbers to be 
of economic importance if the excretion can be utilized as is the exere- 
tion of an allied insect which produces the true white wax of commerce. 
The matter is now being investigated by the chemist of the Cornell 
University Experiment Station, and will probably be discussed in the 
next report of that institution.” Like so many promises, this seems 
never to have been fulfilled, since, at any rate, the Cornell institution 
has never published the results of the chemical! examination. 
Last January the writer received specimens of this insect from Mary 
©. B. Watkins, teacher in the Indian school at Mesa Grande, Cal. 
They were not sent in position on the twigs, but had been removed 
from the twigs and mashed together by hand intow more or less pliable 
lump, somewhat resembling a lump of india rubber, but not possessing 
the same elasticity. The specimen was referred to the chemist of the 
