396 DR. C. F. SONNTAG ON THE ANATOMY, 



The thymic constituent consisted mainly of concentric corpuscles 

 and little lymphoid tissue. These conditions are, however, 

 individual peculiarities. 



The tMjimis (text-fig. 42), lying in the thorax, consisted of a 

 large left part reaching the level of the third costal cartilage, 

 and a small right part reaching the second cartilage. These 

 parts touched over the pericardium and the left part sent a 

 process up under the great veins. Both parts have coarse 

 lobules, and no cavity is present in either. It is supplied by 

 the internal mammary artery, and the veins enter the left 

 innominate vein. 



The spleen is small, measuring 3*8 ins. long, 2-4 ins. wide and 

 1-2 ins. thick. It has the same shape as in Man. The hilum 

 is elongated. A small, oval accessory spleen is present. The 

 artery is smaller than the hepatic artery. Other examples have 

 larger spleens ; but the form and size depend on the stages in 

 digestion. 



The suprarenal capsules are elongated bodies, with rounded 

 ends, lying in the usual positions. They receive their arteries 

 from the phrenic and renal arteries, but none from the abdominal 

 aorta. The suprarenal plexuses are well marked. 



The Blood. 



Gulliver (23) pointed out that the red blood corpuscles have a 

 diameter of 1/3412 inch, whereas those of Man are 1/3200 inch 

 wide. The precipitin reactions have been described by Nuttall 

 (38) who found that the blood of the Chimpanzee gives strong, 

 positive reactions with those of Homo and Sirnia, but he does 

 not mention its reaction with those of Gorilla and Hylohates. 



The Lymphatic System. 



The thoracic duct arises from a receptaculum chyli of con- 

 siderable size by two vessels, which unite later. One vessel runs 

 upwards on the right side of the thoracic aorta, and the other 

 courses on the postei'ior surface of the cesophagus. At the level 

 of the sixth doi-sal vertebra the two vessels unite to form a 

 trunk, which runs up betAveen the oesophagus and vertebral 

 column, and to the left side of the former. It then passes into 

 the neck where it opens into the junction of the left subclavian 

 and jugular veins. 



No right lymphatic duct was detected. 



The lymphatic glands are fewer than in Man, and the following 

 groups were isolated : — 



A. Glands in the Head and Neck: — 1. A row* of small glands 

 lying on the surface of each submaxillary gland ; 2. A group of 

 both lai'ge and small glands between the cleido-mastoid and the 

 larynx ; 3. No glands were found on the surface of the parotid 

 or along the great vessels ; 4. A group of glands over the sub- 

 occipital region. 



