Page:The American Cyclopædia (1879) Volume III.djvu/713

CANKER CANKER WORM 703 remarkable character of this lady has been eulogized by Varnhagen von Ense and Franz Horn, and Canitz's poem on occasion of her death and two of his religious poems are among his most popular effusions. He excelled in satirical and didactic poetry. A selection of his works is in the Bibliothek tier deutschen Dichter des 17. Jahrhvnderts (Leipsic, 1838). CANKER, a form of aphthous liberation of the mucous membrane of the mouth, most com- monly seen in children, and usually connected with derangement of the digestive apparatus. The ulcers are small, circular, superficial, filled with a white thick exudation, sometimes sur- rounded by a circle of inflammation, and very sensitive; they originate in small, hard, red, and painful prominences, which are soon changed into vesicles, whence the name " ve- sicular stomatitis." When the ulcers are few in number they quickly disappear, their cica- trization being hastened by astringent or caus- tic applications, and by the exhibition of gen- tle aperients. In unhealthy children the ulcers are apt to be confluent, and tend to spread to the oesophagus and stomach ; in such cases there may be considerable constitutional dis- turbances, requiring tonics and alteratives. The predisposing cause of aphthae is anything that enfeebles the system, and the exciting cause any irritation in the mouth from foreign bodies, decaying teeth, or acrid food. The usual seat is on the inside of the lower lip and cheeks, and on the tongue, though they may occur on almost any part of the mucous mem- brane. Billard represents them as ulcerations of the muciparous glands or follicles, but in many cases they are too superficial to admit of this explanation. When they occur in debili- tated constitutions, in the course of other dis- eases, they form a painful and dangerous com- plication, from their liability to extend and to take on a gangrenous aspect. They are gene- rally only a local affection, and require for their removal only local applications. The best of these are nitrate of silver, applied either in the solid form or in solution, and borate of s ula, which is often used dissolved in honey. Internal remedies are rarely required. The return of the ulcers may be prevented by at- tention to the general rules of hygiene, and especially to the diet, which should be simple, nutritious, and easily digested. CANKER WORM, the caterpillar of a nocturnal lepidopterous insect, or moth, of the family f/eometrce, Linn, (or phalanites, Lat.), of the group Tiyberniadce, and the genus anisopteryx. In the moths from which canker worms are produced the females are wingless. The males have antennoo with a downy edging on each side ; the wings are large and silky, and when at rest the fore wings entirely cover the hind wings ; the fore wings are ash-colored, with a whitish spot on the front edge near the tip, and two irregular white bands crossing them, with black dots along the sides and outer margin ; the hind wings are pale ash, with a blackish dot 148 VOL. in. 45 near the middle ; the expanse of wings is about 1J inch. This is the common American spe- cies, which is smaller and darker, than the European, and is the A. vernata (Peck) ; there Canker Worm. 1. Adult Male. 2. Larva. 8. Adult Female. 4. Cluster of Eggs. is a smaller species, without the whitish bands and spots, the A. pometaria (Harris). These moths usually come out of the ground about the middle of March, sometimes a little earlier or later, according to the season, and continue to rise for about three weeks ; in mild winters they have been seen in every month from October to March ; the females are most numer- ous in autumn and winter, and the males most abundant in the spring. The wingless females creep up the trunks of the nearest trees, and are followed in a few days by the males, when the pairing takes place ; the eggs are placed on the branches in clusters of 60 to 100, the number usually laid by each female, and are attached by a water-proof varnish ; soon after this the insect dies. The eggs are hatched from the 1st to the middle of May, at the time when the red currant blossoms and the young leaves of the apple begin to start ; the young worms gather upon the tender leaves, and creep into the buds and flowers ; at first they make but small holes, but at last devour all the pulpy part of the leaves of the apple, elm, cherry, plum, lime, and other native and cultivated trees. The worms vary considerably in color within the limits of the same species ; when very young they are of a blackish brown color, with a yellowish stripe on each side, the belly whitish, and two bands of this color across the head ; when fully grown they become ash-colored on the back, black on the sides with a pale yellowish line below it ; some are dull greenish yellow, others green with two white stripes on the back, and others clay- colored ; when full-grown they are nearly an inch in length. After eating for about four weeks, they begin to quit the trees on which they have fed ; some creep down, but most let