250 ARTHUR WILLIAM MEYER 



examination for Hosier especially emphasized the fact that ''das 

 sehr sparsam vorhandene Fettgewebe zeigte nirgends eine nahere 

 Beziehung zur Entwickelung derselben." Moreover Winogradow 

 (53) only reported enlargement and reddening of lymph nodes 

 and not a new formation of anything. The above criticisms 

 also apply, of course, to Warthin's conclusions regarding the 

 production of hemolymph nodes by splenectomy for he too did 

 not state that he took the precaution to carefully examine the 

 abdominal cavity of the animals before the operation was done. 

 Moreover, Warthin did not consider the occurrence and pres- 

 ence of accessory spleens in normal animals and emphasized the 

 impossibility of distinguishing between lymph and hemolymph 

 nodes. 



But even granting that these considerations do not wholly 

 invalidate the conclusions of investigators who reported posi- 

 tive results the negative results of Vulpius (45), Vincent (43), 

 Piltz (28) and Gibson (14) together with those presently to be 

 reported in addition to other considerations certainly would seem 

 to do so. 



Piltz who concluded that there are no hemal nodes in cats 

 and dogs removed the spleen from four dogs but failed to find 

 the formation of hemal nodes in from eight days to three months 

 after operation. Gibson also reported that he found "No naked 

 eye abnormal appearances with the exception of the absence of 

 the spleen" in a dog from which the spleen had been removed 

 five and a half months previously. Similar observations were 

 also made by him on the body of another dog in which both 

 spleen and thyroid were removed. In this animal Gibson stated 

 that he thought that the mesenteric nodes were large as com- 

 pared with the normal but ''not decidedly redder than usual." 

 Practically the same results were obtained by Gibson in an- 

 other dog from which the spleen had been removed and which 

 had been bled 0.5 and 8 per cent of its body weight respectively 

 within an interval of six days. Regarding this animal Gibson 

 stated that the abdominal lymph nodes were "if anything some- 

 what redder in the center than usual," and contained some 

 nucleated erythrocytes. However, that the slight — if any— red- 



