446 



LYMPHATIC SYSTEM. 



the glands, as they are buried sometimes in oedematous swelhngs of 

 varying size. On the other hand, they may be painless on being 

 touched, but swollen, hypertrophied, indurated, hardened or caseous. 



The deep-seated glands of the fore portion of the body comprise 

 the retrO'pharyngeal and the cervical chain running along the posterior 

 border of the trachea. Normally these glands cannot be examined 

 (Fig. 210) ; but when the seat of certain morbid processes, they may 

 be so enlarged as even to be readily visible. The larynx and pharynx 

 are then displaced downwards, the depression between the head and 



f 



G.A 





G.F 



'A 



Fig. 211. — Lymphatic glands of the hind quarter. GG, Precrural lymphatic gland ; 

 GF, lumbar lymphatic ; GP, popliteal lymphatic (deep-seated) ; Gl, ischiatic 

 lymphatic (deep-seated) ; GA, anal lymphatic (deep-seated). 



upper extremity of the neck disappears, together with the depression 

 known as the jugular furrow. Such deformities may be either per- 

 fectly symmetrical, as in lymphadenia, or (as is more commonly the 

 case) asymmetrical, as in tuberculosis ; and if inspection leaves any 

 doubt, the glands may be further examined by palpation. 



To obtain the fullest information both hands should be used, one 

 arm being passed over the neck and the fingers engaged behind the 

 trachea. The operator may also stand in front of the animal, whose 

 head should be lifted so that the points of the fingers can be thrust 

 deeply inwards on either side of the trachea in the direction of the 

 vertebral column. 



