i8o 



Scientific Proceedings (76). 



Normal urine appears to contain between 0.08 and 0.2 per cent, 

 sugar. Urines which give only a slight reaction with Benedict's 

 qualitative reagent give higher figures with this method, generally 

 between 0.25 and 0.35 per cent. The data on the previous page 

 from a human adult, kindly loaned by Dr. Bailey, 1 nicely illustrate 

 several of the points in question. • 



The above results scarcely appear to support the recent con- 

 clusions of Taylor and Hulton 2 regarding the assimilation limit 

 of glucose. If, however, only the twenty-four hour specimen of 

 urine had been examined as in their experiments, the result would, 

 no doubt, have been negative. 



102 (1166) 



Regeneration in the mesencephalon of Amblystoma. 



By H. Saxton Burr. (By invitation.) 



[From the Department of Anatomy of the Yale University School 

 of Medicine, New Haven, Conn.] 



In April of the present year the writer published a report of an 

 experimental study of regeneration in the forebrain of Amblys- 

 toma. The results showed that the removal of the cerebral hemi- 

 sphere together with the end-organ normally connected with it 

 (the nasal placode), was not followed by a regeneration of nervous 

 tissue. On the other hand, when the cerebral hemisphere was 

 was removed, leaving the nasal placode in place as a functionally 

 active organ, complete regeneration of the hemisphere occurred. 

 It was concluded that the functional activity of the nasal placode 

 provided the requisite stimulus, at first through some hormone 

 reaction and later through the active ingrowth of the olfactory 

 fibers, for the regeneration of the hemisphere. 



This spring the same type of experiment has been performed 

 with the ocular complex. Amblystoma larvae were subjected to 

 two series of operations. In the first the right eye and the under- 

 lying mesencephalon was removed. In the second the right eye 

 was turned back with a flap of skin and the underlying brain re- 

 moved, the eye being then returned to its normal position. 



' See Bailey, C. V., Proc. Soc. Exper. Biol, and Med., 1916, XIII, 154. 

 2 Taylor, A. E., and Hulton, F., J. Biol. Chetn., 1916, XXV, 173- 



