Foreign Bodies in the Animal Body. 139 



effect of dipeptids in a similar manner. Leucyl-glycin and car- 

 nosin have been tested. The leucyl-glycin was a synthetic prod- 

 uct. The carnosin was obtained from muscle. It was prepared 

 by Dr. D. W. Wilson. 



Both of these substances are toxic in large doses. Their 

 toxicity is not as marked, however, as is that of the o-amino acids. 

 The leucylglycin is more toxic than the carnosin. 



During the course of these experiments we prepared and tested 

 peptones prepared from beef. These were found not to affect in 

 any way the growth of the cells. 



192 (1370) 



A note on the healing in and migration of foreign bodies in the 



animal body. 



By L. S. N. Walsh and Leo Loeb. 



[From the Department of Comparative Pathology, Washington 

 University, St. Louis.] 



We have made some observations on the difference in the be- 

 havior of different species of animals towards foreign bodies on 

 which we wish to report very briefly. 



If we apply very thin wires of copper around the neck of white 

 rats in such a way that apparently they do not exert any marked 

 pressure on the skin, these wires heal in at the ventral aspect of 

 the neck, but not at the dorsal and lateral aspects, in a considerable 

 number of cases, after they have at first produced some ulceration. 

 About four weeks after the onset of the ulceration the skin begins 

 to heal over the wire and soon the wire is buried deep in apparently 

 normal tissue. Gradually the wire may migrate deeper into the 

 tissues of the ventral parts of the neck and in one case it was found 

 resting on the trachea, the tissues covering it being apparently 

 quite normal. Thus the migration of foreign bodies can be imi- 

 tated experimentally in certain cases. 



In a large number of white mice and in three guinea pigs wires 

 which had been applied in a similar manner, or even somewhat more 

 tightly, did not heal in, but led to a transitory, more or less, super- 

 ficial ulceration and scab formation. After some time such ulcers 



