SHEPHERDING AND PASTURING 343 



hatch. When it is above that they will hatch out in a 

 few hours or in a week or so, depending upon how warm 

 it is. Freezing or drying soon kills the unhatched eggs. 

 So it is seen that ewes will not pollute a field in winter, 

 their droppings are sure to be soon frozen, at least in 

 the region where sheep are mostly kept. But if the tiny 

 worm hatches from the egg it feeds for a time upon the 

 material of the manure and continues to grow till it is 

 about one-thirtieth of an inch long. Then it creeps up 

 on a blade of grass and waits to be swallowed by some 

 kmb, after that it finishes its growth within the fourth 

 stomach of the lamb, and, incidentally, finishes the lamb 

 as well. The ewe flock should be treated for stomach 

 worms. -This is best done in the fall, when they come 

 from pasture. It may be again done in the spring before 

 their lambs come. The use of some of the coaltar dips, 

 in small doses, much diluted, will eventually be recog- 

 nized as most efficient. This treatment alone has doubled 

 the weight of lambs in some experiments in Kentucky. 

 Next, the flock should at the approach of spring weather 

 be confined to the yard and shed. There are two reasons 

 for this : it is better for the grass, and thus in the long 

 run better for the flock, and there is no contamination of 

 land over which the lambs will later feed. If it were 

 possible wholly to eradicate the worms from the ewes 

 by treatment this care would not be needed, but unfortu- 

 nately it seems almost impossible with our present knowl- 

 edge to kill all of the worms by any medication.' While 

 confined to the yard the lambs will probably be born. It 

 is essential that the flock be well fed at this time, so that 

 the ewes will be full of milk. If desired they may be 



