36 



Scientific Proceedings (51). 



pulp of the spleen. The method used by Payr in transplanting 

 thyroid tissue was followed. In four animals (2 dogs and 2 cats) 

 pancreatic cells were demonstrable in the spleen. The interval 

 between the operation and the death of the animal varied from 

 18 hours to 13 days. In five animals (all dogs) no pancreatic 

 remains were found. Autolysis was rapid. In one experiment 

 all the pancreatic cells had disappeared 21 hours after the trans- 

 plantation. The bit of tissue found 13 days after the transplant 

 measured only 1 mm. by 0.1 mm. It consisted of normal appear- 

 ing acini surrounded by connective tissue. No islands of Langer- 

 hans were demonstrable. 



In one dog a large pancreatic graft was placed in the spleen 

 with the blood supply preserved by means of a mesenteric stalk. 

 Three weeks later the original blood supply was cut off and all the 

 pancreatic tissue except the graft extirpated. Diabetes did not 

 develop, but the tolerance for glucose fell within a few weeks 

 to a low point. At the autopsy 187 days after the second operation 

 a large abscess was found in the lower part of the spleen. Pro- 

 jecting into the spleen from the wall of the abscess was a cone- 

 shaped mass of fibrous tissue. In this were the remains of the 

 pancreatic transplant measuring less than 1 cm. in length. The 

 pancreatic tissue consisted of acini separated by connective 

 tissue. In some of the cells, masses of zymogen granules were 

 present. These were no demonstrable islands of Langerhans. 

 This experiment proves that pancreatic tissue implanted in the 

 spleen and separated from its original vascular and nervous con- 

 nections can live and functionate for months. 



26 (722) 



The production of reversed cardiac mechanism in the dog. 



By Alfred E. Cohn. 



[From the Hospital of the Rockefeller Institute for Medical Research, 



New York.] 



In a series of experiments, which were published with Kessel 

 and Mason, 1 on the excised perfused hearts of dogs, we were able 

 to show that "excision of the sinus node results in an immedate 



1 Heart, June 15, 1912, iii, 311. 



