TICK (AS. ticia, miswritten for tiica, tica, Ger. Zecke, tick; connected with Arm. tiz, tick). One of those members of the order Acarina which belong to the families Argasida. and Ixo didfe, which have been grouped together in the superfamily Ixodoidea. The ticks or 'louse-flies' are eight-legged creatures in which the cephalo thorax is coalesced with the abdomen. The young, newly hatched individual is flat and near ly circular and has only six legs. With the first molt it enters the second or nymphal stage, which is characterized by the presence of a fourth pair of legs. After the second molt it be comes mature. In the free-living state the body of a mature tick is flattened dorsally and is of an oval shape. The body is covered with a leathery integument which generally assumes on the dorsal surface a hardened, chitinous. more or less smooth, and darker appearance. Near the margin it is impressed by a depressed line leaving a distinct rim around the body.
All ticks, so far as known, although found upon plants in their early stages, are parasites of animals. The young seek on every possible occasion to fasten themselves to vertebrate ani mals. Mammals and birds seem t-o be preferred, and spots where the skin is soft are chosen. When the very young first fasten themselves they cannot penetrate deeply enough to draw blood, but the irritation causes a suppuration on which they feed. When, however, they have grown sufficiently to enable them to reach a blood-ves sel, the small, flat, semitransparent creatures soon become distended, the body becomes rounded, and the color frequently becomes dark red. In a week or more the larva is transformed into the nymph, which at the expiration of another week is changed to a mature individual. The female only sucks blood, so far as is known. The male retains its form and size, and although it at taches itself to warm-blooded animals, it evident ly does so only for the purpose of seeking the female.
Several species occur in the United States. The common dog tick or wood tick (Dermacentor elect us) is found frequently in the woods in the Northern States. The common tick occurring upon the ground-squirrel in the Mississippi Val ley is /xodcs ricinus. degas miniat as is very de structive to chickens in parts of Texas and Florida, and Argus reflexus, the pigeon tick, is common in pigeon-houses in both Europe and the Southern United States. This species is capable
of living an almost incredible length of time without food. In Persia a species, the miana-bug Persiccr), lives in houses and seeks its human prey at night; its bite causes serious disturbance, and is said even to cause death. In South America a species known as 'garapate' (.4 inblyomina Americanum) occurs in dry, bushy places, where it clings to twigs and transfers it self to passing horses or cattle as opportunity oc curs. It also lives in the United States and has been found on human beings. Eight species of ticks in the United States have been found upon cattle, one associated with the Texas cattle fever (Boophilus annulatus) being the most noted and the most destructive. Other species of the same genus transmit the same or similar dis eases of cattle in other parts of the world. Bodphllus australis transmits what is probably the same disease in Australia, and Boophi/us deco/ma/hi& (the so-called 'blue tick') acts the same way in South Africa, carrying the disease commonly known as 'red water.' Texas cattle fever is particularly destructive to Northern cattle that have been shipped south or that have been brought into contact with Southern infested cattle which have been shipped north. The dipping of cattle in vats containing cottonseed oil or any one of several mixtures, known at 'cattle dips,' destroys the ticks.
Certain mites of the family Gamasithe are sometimes known as ticks, although the name in this application is erroneous. The bird tick (Dermanyssus arium) is a familiar parasite of caged birds. The poultry tick (Dermany&sus which is also known as the 'little chicken mite,' gathers on fowls in the hennery, especially at night, and sucks their blood. Cer tain of the true insects are also erroneously called ticks. For example, the flies of the family Hip poboscithe are quite generally known as bird ticks. (See FOREST FLY and PuraPARA.) The degraded wingless flies of the family Nycteri biidie are called bat ticks.
Consult: Osborn, Insects Affecting Domestic Animals (United States Department of Agricul ture, Washington, 1896) ; Salmon and Stiles, Cattle Ticks of the United States (ib., 1902) ; Marx, "Classification of the Ixodidfe," in Pro ceedings Entomological Society of Washington, vol. ii., No. 2 (1392) ; Marx, "The Morphology of the Ticks," id., vol. ii., No. 3 (1892).