120 GLANDERS AND FARCY. 



and fowls, and to be less active when introduced into the horse 

 in this way. Although it may thus be propagated both medi- 

 ately and immediately, directly or by a secondary agent or 

 carrier, the virus itself is only capable of multiplication Avithin, 

 not without, the animal body. In this latter situation it is 

 distributed by the blood and serous canals, and partly by the 

 inspired air. 



h. Anatomical Characters. — The anatomical features pecu- 

 liar to glanders, which a naked eye examination takes cogni- 

 sance of, are mainly embraced in the existence of certain 

 neoplastic growths, nodules or tubercles, in certain situations 

 and tissues for which they have a special affinity, or of diffuse 

 infiltrations in certain organs and textures. These growths 

 occur chiefly in the mucous membrane of the air-passages, as 

 the membrane lining the nasal chambers, the sinuses of the 

 head, the larynx and the trachea, and in the lungs and pleura. 

 They are likewise encountered in the skin and subcutaneous 

 connective tissue, the muscles, and in certain internal organs, 

 as the liver, the spleen, kidneys, etc. The lymphatic vessels 

 and glands are similarly affected. 



When the tubercular form of glanders occurs on the mucous 

 membrane of the air-passages— the situation most obviously 

 invaded — the form is that of raised or slightly elevated nodules 

 on an inflamed and indurated base, surrounded by a ring or 

 zone of similarly indurated and vascular character ; they are 

 of a tolerably firm consistence, light in colour, and in their 

 centre prone to disintegration and the formation of ulcers. 

 The surface of these sores is glistening, covered with a sticky 

 puriform fluid mingled with blood. These ulcers have a ten- 

 dency to extend, occasionally involving the underlying tissues, 

 whether cartilage or bone. 



In the lungs these tubercles present an appearance somewhat 

 like the milliary tubercle of man, but in less masses. To the 

 naked eye they appear as small circumscribed spots of con- 

 gested tissue, or as lirmer indurated nodules, with an encircling 

 hyperasmic zone and a soft 3^ellowish centre. In substance 

 they are chiefly composed of proliferating nucleated cells of 

 varying size, apparently depending upon their ago and period 

 of growth. After a certain time, these cell elements are prone 

 to undergo change ; they lose their distinctive characters. 



