EXTIRPATION OF THE SPLEEN 383 



this takes place in the human subject, and the movements are so slow 

 and inefficient that it does not appear that they can either promote or 

 retard the flow of blood. 



Extirpation of the Spleen. Removal of the spleen is an old and 

 a very common experiment. In the works of Malpighi (1687) is 

 an account of an experiment on a dog, in which the spleen was de- 

 stroyed and the operation was followed by no serious results. Since 

 then it has been removed so often and the experiments have been 

 so often negative in their results that it is hardly necessary to cite au- 

 thorities on the subject. There are many instances, also, in which it has 

 been in part or entirely removed from the human subject, which it is un- 

 necessary to refer to in detail. One of the phenomena following extir- 

 pation of the spleen is a modification of the appetite. Great voracity in 

 animals after removal of the spleen was noted by the earlier observers. 

 Later experimenters have observed this change in the appetite and have 

 noted that digestion and assimilation do not appear to be disturbed, the 

 animals becoming unusually fat. 



In the following observation these phenomena were well marked : 



The spleen was removed from a young dog weighing twenty-two 

 pounds (about 10 kilograms). Before the operation the dog presented 

 nothing unusual, either in his appetite or disposition. The wound 

 healed rapidly, and after recovery had taken place, the animal was fed 

 moderately once a day. It was noticed, however, that the appetite was 

 voracious. The dog became so irritable and ferocious that it was dan- 

 gerous to approach him, and it became necessary to separate him from 

 the other animals in the laboratory. He would eat refuse from the 

 dissecting-room, the flesh of dogs, feces etc. About six weeks after 

 the operation, having been well fed twenty-four hours before, the dog 

 ate at one time a little more than four pounds (1814 grams) of beef- 

 heart, nearly one-fifth of his weight. This he digested well, and the 

 appetite was undiminished on the following day. The dog had a 

 remarkably sleek and well-nourished appearance (Flint, 1861). 



The above is a striking example of the change in the appetite and 

 disposition of animals after extirpation of the spleen ; but these results 

 are by no means invariable. In many instances of removal of the spleen 

 from dogs, the animals were kept for several months and nothing 

 unusual was observed. On the other hand, the change in disposition 

 and the development of an unnatural appetite were observed in animals 

 after removal of one kidney. These effects were also marked in an 

 animal with biliary fistula that lived for thirty-eight days. In the latter 

 instance, the voracity could be accounted for by the disturbance in 

 digestion and assimilation produced by shutting off the bile from the 



