LOUPING-ILL. 00/ 



said to present symptoms of the disease during the lonping- 

 ill season. 



When they first leave the ground to attack animals they are 

 very small, sometimes no larger than a pin's head, and when 

 very numerous make the part quite black by their numbers, 

 and they adhere so closely that scraping them off Avill tear up 

 the skin. 



13eiug satisfied that the parasites had a close connection 

 with the disease (the proofs that they were co-existent upon 

 certain lands, and simultaneous in their appearance, being over- 

 whelming), but failing to see that they caused grave disease 

 and death by inducing irritation and loss of blood to any great 

 extent, it was necessary to discover if any oiganism existed in 

 sheep dead from louping-ill, and if so, to tiace its source of 

 origin, indeed to demonstrate if such an organism was common 

 to the tick and to animals affected with louping-ill. This was 

 a matter of some difficulty, as in the majority of tlie animals 

 examined after death no really characteristic lesions could be 

 detected. 



In many, all parts of the body presented the appearances of 

 health, death having been evidently due to intense nervous 

 irritation. 



In some, of course, it will be understood that there were signs 

 of other diseases, but these in reality had no connection with 

 the animal's death, and we are now referring to louping-ill 

 pure and simple. In some instances there is a jelly-like for- 

 mation within the spinal canal, sometimes extending in a more 

 or less uniform layer from one end of the canal to the other, 

 but rarely extending within the cranium. It is sometimes 

 in patches here and there, particularly embracing the roots 

 of the spinal nerves ; generally there is a large patch in the 

 lumbar region, then smaller ones scattered along the dorsal 

 region ; often a large patch at or about the junction of the 

 cervical and dorsal, and very frequently a large and much 

 redder patch immediately posterior to the foramen magnum, or 

 entrance into the brain cavity. This jelly is seen both in lambs 

 and in aged sheep in great perfection. It was first seen in 

 sheep by me at Langholm on 20th May 1881, in a four-year- 

 old ewe. I have also seen it in oxen, as well as in sheep 

 and lambs. It is, however, not constant, even in cases that 



