70 VETERINARY STATE BOARD 



tation (receptaeulum chyli), passes forward through the pillars 

 of the diaphragm to the sixth dorsal vertebra, where it passes to the 

 left and empties, after a dilatation, into the anterior vena cava at 

 the junction of the jugulars. 



Describe the lymphatic glands. 



The lymphatic glands are ovoid, spherical or discoid bodies of 

 medium consistency, which intercept the course of lymphatic vessels 

 at several points. Their number is considerable, and they are rarely 

 single, but most frequently are collected in groups along the blood- 

 vessels. All the vessels of the lymphatic system are provided with 

 one or more of these glands on their course. The branch of the 

 vessel, entering the gland, is called the afferent, and that leaving, 

 the efferent. The capsule of the gland sends fibrous strands into its 

 substance, dividing it into very minute spaces (lymph sinuses) 

 which are filled with lymph corpuscles. The afferent vessels take a 

 tortuous course and, communicating with the sinuses, become 

 charged with lymph-cells. 



Lymph-glands are richly supplied with blood-vessels which 

 penetrate the gland through the capsule, or enter at the hilum and 

 break up into a fine-meshed capillary network, branches of which 

 pass through the lymph sinuses. 



The lymph-glands act as filters for the lymphatic system and are 

 important as a source of leucocytes. 



In what part of the intestinal tract is lymphoid tissue found ? 



At certain places in the walls of the ileum there are collections 

 of solitary follicles, known as Peyer 's patches. 



Give the situation of the lymphatic glands of the thorax. 



1. Posterior mediastinal, a series of small granular masses on the 

 course of the oesophagus. 



2. The bronchial, in the angle of the bifurcation of the trachea. 



3. Two long strings of lobules which extend on the sides of the 

 inferior face of the trachea, from the base of the heart to near the 

 first rib. 



Mention the location of the following lymphatic glands: posterior 

 cervical, prescapular, posterior mediastinal, inguinal, popli- 

 teal, precrural, iliac, axillary and bronchial. 



Posterior cervical, situated on the side of the terminal extrem- 

 ity of the jugular, within the inferior border of the scalenus muscle, 

 extends into the chest by passing beneath the axillary vessels and 

 ascends to the inner face of the first rib. 



Prescapular, situated on the ascending branch of the inferior 



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