328 PARASITES OF ANIMALS 



cases the back becomes hollow, and there is a corresponding 

 pendulous condition of the abdomen. The spinal columns ulti- 

 mately stick out prominently, forming the so-called "razor- 

 back." As Professor Simonds has well observed, in an earlier 

 stage of the disease, " an examination of the eye will readily 

 assist in determining the nature of the malady. If the lids are 

 everted it will be found that the vessels of the conjunctiva are 

 turgid with pale or yellowish colored blood, the whole part 

 presenting a peculiar moist or watery appearance. Later on, 

 the same vessels become blanched and scarcely recognisable." 

 The skin also becomes harsh and dry, losing its natural tint, 

 and the wool is at length rendered brittle, either becoming very 

 easily detached or falling off spontaneously. 



The first thing noticeable in dissecting a rotten sheep is the 

 wasted and watery condition of all the tissues. There is a 

 total absence of that firm, fresh, carneous look which so dis- 

 tinctively characterises the flesh in a state of health. Not only 

 is the. rigidity and firm consistency of the muscles altogether 

 wanting, but these structures have lost that deep reddish color 

 which normally exists. When the abdominal cavity is opened 

 a more or less abundant, clear, limpid, or yellowish fluid will 

 make its escape, and the entire visceral contents will, at the 

 same time, display a remarkably blanched aspect. These 

 pathological changes are also shared by the important organ 

 especially affected, namely, the liver. This gland has lost its 

 general plumpness, smoothness, and rich, reddish-brown color, 

 and has become irregularly knotted and uneven both at the 

 surface and the margins, its coloring being either a dirty 

 chocolate brown, more or less strongly pronounced at different 

 parts, or it has a peculiar yellowish tint, which in places is very 

 pale and conspicuous. To the feel it is hard and brawny, and 

 when incised by the scalpel, yields a tough and, in places, a 

 very gritty sensation. On opening the gall-ducts a dark, thick, 

 grumous, biliary secretion oozes slowly out, together with 

 several distomes, which, if not dead, slowly curve upon them- 

 selves, and roll up like a slip of heated parchment. On further 

 slitting open the biliary passages, they are found distended 

 irregularly at various points, and in certain situations many 

 flukes are massed together, having caused the ducts to form 

 large sacs, in which the parasites are snugly ensconced. The 

 walls of the ducts are also much thickened in places, and hard- 

 ened by a deposit of coarse calcareous grains on their inner 



