THE SUPPOSED EXPERIMENTAL PRODUCTION OF 



HEMOLYMPH NODES AND ACCESSORY 



SPLEENS 



V. STUDIES ON HEMAL NODES 



ARTHUR WILLIAM MEYER" 



From the Division of Anatomy of the Department of Medicine, Stanford University 



For some decades it has been customary to speak of at least 

 two types of lymph glands or nodes — the ordinary lymphatic 

 gland and the hemolymph node. Although these two types of 

 nodes have been said to occur in man (2, 3, 5, 11, 17, 20, 21, 

 28, 38), monkeys (17, 37, 37 a), rodents (18, 36, 44), most of the 

 domestic animals (2, 3, 4, 5, 6, 11, 12, 18, 21, 29 a, 36, 37, 38, 

 39, 44, etc.), birds (18, 36, etc.), fish (36, 37 a), and so forth, 

 those who studied them in greater detail soon found that neither 

 gross nor microscopical difTerentiation was possible because all 

 manner of transition or intermediate forms were thought to exist. 

 Vincent and Harrison (42), for example, make the following 

 statement : 



We believe that we have found gradual transitions from hemolymph 

 glands on the one hand, to ordinary lymphatic glands, and on the 

 other hand, to the structure of the spleen. So that no hard and fast 

 line can be drawn marking off these structures from one another. A 

 lymphatic gland has only to contain blood in part or the whole of its 

 sinuses to constitute itself one of the varieties of hemolymph glands. 

 In certain 'accessory spleens' moreover, the splenic reticulum is so 

 widened out as to approximate to a blood sinus of a hemolymph gland 

 and the Malpighian bodies are so diffuse as to resemble the lymphoid 

 portions of the blood-lymph glands. So that spleen, hemolymph glands 

 and ordinary lymphatic glands form almost a continuous series. 



A similar opinion was subsequently expressed by Warthin who 

 further satisfied himself that hemolymph nodes can be produced 

 experimentally and that there is a transition from fat to hemo- 

 lymph nodes to lymph glands and back again to fat. 



241 



