130 CRABS AND INSECTS. 
deposited on the water, and the larve breathe by a star- 
shaped organ at the hinder extremity, through which air 
passes to the trachee. They finally shed their skins and 
Fic. 163.—Antenna of mos- 
quito, magnified. 
appear as pupe, in which state 
they breathe through two tubes 
in the thorax. In a few days 
the skin breaks between the 
breathing-tubes and the insect 
emerges, and, after floating 
about for a while on the old 
skin as a raft, it flies away a 
perfect insect. 
Note.—In the small town of Elizabethport, Russia, in the month 
of June, 1830, 30 horses, 40 foals, 70 oxen, 90 calves, 150 hogs, and 
400 sheep were killed by mosquitoes alone. The females generally do 
the most damage. 
Works on Diptera for further ve ference. 
“Transformations of the Common 
House-Fly, with Notes on Allied Forms,” 
A. S. Packard, Jr., “‘ Proceedings of the 
Boston Society of Natural History,” vol. 
xv; ‘‘Catalogue of Described Diptera of 
North America,” R. Osten-Sacken, in 
“Smithsonian Miscellaneous Collections,” 
vol. iii, No. 1, 1862; ** Animal Parasites 
and Messmates,” Van Beneden. 
Order VII. Butterflies and 
Moths (Lepidopter a).— General 
Characteristics.—Small-headed _in- 
sects with four wings, which with the 
body are covered with scales; the 
tongue consisting of two tubular or 
hollow threads adapted for suction, 
and coiled when not in use; meta- 
morphosis complete, the larve or 
caterpillars having abdominal legs. 
Fic. 164.— Head of 
Sphinx- moth, show- 
ing coiled tongue, and 
pollen-masses that have 
been taken from some 
flower, attached to the 
eyes. 
