. Animal parasites and human disease. Insects as carriers of disease; Medical parasitology. 520 ILV MAGGOTS AND MYIASIS. (Fig. 250B) are white, footk'ss creatures, jjrovidod with a pair of stout h() near the mouth, and witli of minute whieli p;ive them a screwhkc appearance, whence the^' derive their name. Eating away at flesh and even l)()ne, they develop rajiidly to a length of about half an inch, and maturit}' maj' be reached in three d a y s, though four or five days is usuall}' recjuired. When fully developed the larva leaves its feeding grounds and buries in l
. Animal parasites and human disease. Insects as carriers of disease; Medical parasitology. 520 ILV MAGGOTS AND MYIASIS. (Fig. 250B) are white, footk'ss creatures, jjrovidod with a pair of stout h() near the mouth, and witli of minute whieli p;ive them a screwhkc appearance, whence the^' derive their name. Eating away at flesh and even l)()ne, they develop rajiidly to a length of about half an inch, and maturit}' maj' be reached in three d a y s, though four or five days is usuall}' recjuired. When fully developed the larva leaves its feeding grounds and buries in earth nearb}', where it pupates in two or three da\'s. The pupa^ are brown in color, and shaped somewhat like olives. After four days or more in the pupal the adult insect emerges, climbs up on nearby herbage and rests in a characteristic position with the head down. The Fig. (). Scrow-worm flv, CochUomyia (or i i ir i Chrysomyia) macellaria, adult and maggot, ^^liole life Cycle OCCUpieS X 3. (Adult after Castellani and Chalmers, from nine dayS tO twO larva after Rlanehard.) , weeks or more. As remarked before, the female screw-worm fly, about to re- produce, is attracted to any animal smell and frequently finds a suitable place for egg-laying in exposed wounds, or in the nose or ears of people sleeping out doors, especially in case of foul-smell- ing catarrh. Sometimes the flies select recently vacated Dcr- matobia nests, boils, sores, etc., for the young to develop in. As soon as hatched the maggots begin eating their way into the tissues with which they are in contact, using their strong man- dibles as nippers for cutting flesh and excn bone. From th(^ ear they may make their way into the iimer ear, completely de- stroying the auditory apparatus. From the nose they penetrate to the pharynx, frontal sinus, the eye-ball, and even the brain, occasionally doing such extensive damage as to death. I'sually an abundant discharge of pus and scraps of tissue, in
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectmedical, bookyear1918
