The =Lung Worm= of Lambs (_Strongylus filaria_). Male an inch, female as much as three and a half inches long, thread-shaped, white or yellowish. It appears that the young worms are taken into the stomach of a lamb (or sheep) with the drinking water; they are found there in May, June, and July. They quickly climb back into the throat, from which they get into the windpipe and its branches. There they penetrate the mucous membrane, where, until they have reached the sexual stage, they are found imbedded in small swellings, which they quit at the end of winter or the beginning of the next spring, if their host lives so long. The female bears living young, which as very minute worms may be met with by the hundred in the mucous lining the windpipe and its branches. A direct transference of the parasite from one sheep to another does not take place, since the young born in the mucus secreted by the walls of the air-tubes must first live and grow for some time in water or slime before they are able to undergo further development in the body of a sheep or lamb. The fate, however, of the young worms which pass to the exterior in the mucus is not yet sufficiently known. _Symptoms of Disease_: Running of slime from the nose, difficulty of breathing, cough, emaciation, poverty of blood. Death ensues in from two to four months. Recovery only of very strong individuals infested by comparatively few parasites, most of which they cough out. _Preventive Measures_: In regions where the evil is very prevalent the young sheep must not be allowed to go into the meadows. If it is impossible to keep them penned in, a little food and water may be given before sending them to pasture in the morning. In this way the danger of infection will be somewhat lessened, since it is then less likely that the animals will eagerly betake themselves to pools and ditches in order to quench their thirst. Since during the months May to July the young worms (most probably taken in with the water drunk) are found in the stomach, it is good during this time to give vermifuges to the lambs and sheep. For medicines a veterinary surgeon should be consulted. The =Small-tailed Palisade Worm=, or =Strongyle= (_Strongylus micrurus_). Thread-shaped; male one and two-fifths, female two and two-fifths to two and four-fifths of an inch long; lives in oxen (especially calves) in swellings of the arteries, also in the windpipe and its branches. Severe bronchitis. Family: =Trichotrachelidæ= (_Whip Worms_). Small, slender, elongated worms, with the anus or, in the male, cloacal aperture at the hinder end of the body; the latter, however, is not—as in palisade worms—surrounded by an umbrella or cup-shaped expansion. Here belongs: =The Trichina= (_Trichina spiralis_). [Illustration: FIG. 130.—Encapsuled Muscle Trichinæ in flesh, strongly magnified. ] [Illustration: FIG. 131.—Male Intestinal Trichina, strongly magnified. ]