246 ARTHUR WILLIAM MEYER 



warrant his former conclusions! Tizzoni also failed to specify 

 what the results in this case were and then stated that the acces- 

 sory spleens which form as a result of splenectomy always arise 

 as Malpighian corpuscles which become surrounded by pulp later 

 while on the contrary, in the case of spleens that arise as a result 

 of pathological conditions, the pulp forms first and the rest of 

 the spleen from it. 



In May, 1882, Griffini (15) reported a series of experiments on 

 the regeneration of small experimentally-produced defects of the 

 spleen in fourteen dogs and added that in a few cases he noticed 

 a new formation of spleens from the great omentum or from the 

 spleen itself because of conditions not yet determined. However, 

 Griffini also failed to give any further details regarding these 

 accessory spleens. 



A year later Tizzoni (39) reported that he did splenectomies 

 on two dogs which possessed accessory spleens before operation 

 ''as a result of disease." In one animal which was killed six 

 months after operation there was no increase in size and number 

 of the accessory spleens previously present in the great and gastro- 

 splenic omenta but many newly formed spleens were found in 

 the gastro-hepatic omentum, in the lateral ligament of the blad- 

 der, in the plica Douglasii, in the ischio-rectal fossa, in the serosa 

 of the stomach and in the central tendon of the diaphragm. 

 In the second animal killed seven months after splenectomy, 

 Tizzoni concluded that there was perhaps an increase in size and 

 number of the accessory spleens previously present in the great 

 and gastro-splenic omentum and that in addition other newly 

 formed spleens in all stages of development were found as in the 

 previous animal. Since the first animal had suffered from post- 

 operative local peritonitis Tizzoni concluded that these inflam- 

 matory processes inhibited the formation of accessory spleens in 

 the gastro-splenic and great omentum and lead to their for- 

 mation elsewhere. 



Even granting that Tizzoni was still unbiased and not on the 

 defensive it is perfectly evident that all the additional accessory 

 spleens which Tizzoni regarded as having formed de novo because 

 of splenectomy may just as well have formed because of condi- 



