183 



be killed with the stock chloroform and then removed from the wound 

 before the repellent dressing is applied. The following are successful 

 repellents : — A powder consisting of 80 parts (by weight) powdered 

 alum, 60 parts zinc oxide, 30 parts powdered l)oric acid and 6 parts 

 gum camphor ; or a powder of 5 parts gum camphor, 100 parts powdered 

 charcoal, 50 parts laundry starch, 10 parts boric acid and 10 parts 

 tannic acid. An efficient liquid repellent is composed of 1 quart 

 each of pine tar and machine oil, and 1 lb. chloroform (U.S.?.) and 

 4 oz. gum camphor. Wlien required, one part of the chloroform 

 mixture should be used with four parts of the oil mixture. Other 

 formulae are 4 oz. pine tar, 6 oz. castor oil, 10 oz. kerosene oil and 1 oz. 

 turpentine ; or, 20 oz. pine tar, 10 oz. glycerine and 1 oz. turpentine. 



Practices in range management that tend to prevent outbreaks 

 of screw-worm cases are discussed, such as suitable fencing, the best 

 season for breeding stock, and for dehorning cattle, and the avoidance 

 of overstocking. 



Eiiphormia [Phormia) rcgina, Meig. (black blow-fly or wool maggot) 

 is the real wool-maggot fly of Texas. It seldom appears before 

 October and increases throughout November. During cold weather 

 it is not active, but quickly appears on warm days in January and 

 February. To reduce its numbers, dehorned cattle should have a 

 pine-tar dressing or a good dusting powder applied to the wound. 

 The burning of carcasses and the use of traps for C. macellaria will 

 also destroy many of the blow-flies. 



Bennett (D. H.). Internal Parasites affecting Sheep and Goats.— 



Texas Agric. Expt. Sta., College Station, Circ. 28, AprU 1921, 

 16 pp., 9 figs. [Received 31st\A.ugust 1921.] 



The sheep bot [Oestrus ovis) deposits larvae in the nostrils of sheep 

 and goats, the gi'eatest infestation occurring during the hot periods 

 of the year, but also taking place on warm days in late autumn, 

 winter and early spring. During fly attacks sheep stand huddled 

 in the shade, protecting their noses either in the grass or under other 

 sheep. 



The most pronounced symptoms are seen when the larvae work 

 their way to the upper air passages of the head and horns. During 

 this time a mucous nasal discharge is seen. This stage generally occurs 

 in the summer or early autumn. In about 6-8 weeks the larvae 

 become stationary, and the secretion decreases ; when mature, they 

 descend to bury themselves in the ground to pupate. Practically 

 the same symptoms may be seen during the descent as during the 

 invasion. 



No safe remedy has yet been found, as one strong enough to kill 

 the larvae would probably kill the animal through imtation of the 

 mucous membrane. The f oho wing method is recommended : — 

 A plank with holes bored at intervals should be placed over a salt 

 trough. The salt should be kept at such a level that the nose of the 

 animal, when licking it, must touch the edge of the holes. The 

 entire surface of these holes should be smeared once every three 

 days with 1 pint white pine tar to 2 oz. oil of eucalyptus. Larvae 

 deposited in this mixture smeared on the animal's nose usually die. 

 The mixture may also be smeared with a brush on the nose and 

 adjacent parts at least every week or ten days. The latter method 

 is practicable only for young animals or registered stock. 



