THE ABSORBENTS. 119 



formed by the union of the superior mesenteric and splenic veins, the inferior 

 mesenteric joining the splenic, which also receives one of the gastric, the other 

 emptying into the portal. 



Name the Cardiac Veins. They return the blood from the tissue of the 

 heart into the right auricle. They are the 



Great Cardiac Vein. Anterior Cardiac Veins. 



Posterior Cardiac Vein. Vena Thebesii. 



Coronary Sinus, is a dilatation of the great cardiac vein, receiving the pos- 

 terior cardiac and an oblique vein from the left auricle. 



Describe the Pulmonary Veins. They alone of the veins carry arterial 

 blood, beginning in the capillaries of the lungs, forming a single trunk for 

 each lobule, which, uniting into a single trunk for each lobe, form two main 

 trunks from each lung which open separately into the left auricle. Sometimes 

 the 3 lobe-trunks of the right lung remain separate to their termination in the 

 auricle, and not unfrequently a common opening serves for the 2 left pulmo- 

 nary veins. 



THE ABSORBENTS. 



What are the Lymphatics ? They are very delicate, transparent vessels, 

 formed of three coats like arteries and veins, found in nearly every part of the 

 body, except the brain, spinal cord, eyeball, cartilage, tendons, membranes of 

 the ovum, placenta, umbilical cord, nails, cuticle, hair, and bone. They are 

 nourished by nutrient vessels, and have valves, but no nerves, so far as known. 

 They convey lymph to the blood. 



What are the Lacteals ? They are the lymphatics of the small intestine, 

 conveying the chyle therefrom into the blood. 



What are the Lymphatic Glands? Small solid bodies placed in the 

 course of the absorbent vessels, and found chiefly in the mesentery, along the 

 great blood-vessels, in the mediastina, axilla, neck, front of the elbow, groin, 

 and popliteal space. The lymphatics and lacteals before entering these glands 

 break up into smaller branches, the afferent vessels, which form a plexus in 

 the gland, and pass out as efferent vessels to unite again in one trunk. They 

 also contain spheroidal bodies about J^Q-Q inch in diameter. These glands 

 are named after the regions in which they are situated, as the axillary, inguinal, 

 mesenteric, etc. 



Describe the Thoracic Duct. It is the main channel for the lymph and 

 chyle from the whole body except the right arm and lung, right side of the 

 head, heart, neck, and thorax, and the convex surface of the liver. It begins 

 in the Receptaculum Chyli, in front of the 2d lumbar vertebra, passes through 

 the aortic opening in the diaphragm, and at the upper border of the 7th cer- 



