146 SCIENCE PROGRESS. 



no protamine is to be obtained from the spermatozoa both 

 of oxen and hogs. It is remarkable to find that the chro- 

 matin of such cells as the spermatozoa should chemically 

 consist of substances which relatively to proteids are of 

 simple constitution. If it be true that hereditary charac- 

 teristics are transmitted by the chromatin of the reproduc- 

 tive cells we should have expected a most complex chemical 

 structure for these parts, and it therefore becomes the more- 

 striking to note that the most complex protamine obtained,, 

 arbacin, is from the animal lowest in the scale, and that in, 

 the higher vertebrates examined no protamine is present, 

 at all. 



THE FORMATION OF URIC ACID. 



Following on his discovery of a group in the nuclein 

 molecule, which yielded alloxur-bases, Kossel suggested 

 that the nucleins might prove the source of the uric acid 

 excreted by animals. The first direct evidence in favour 

 of this view was, however, first supplied by Horbaczewski 1 

 who found that if spleen pulp be mixed with blood and a. 

 stream of air passed through it, on keeping this at body 

 temperature for a few hours the xanthine bases gradually 

 disappeared and uric acid appeared in their place. The ex- 

 periments of giving the alloxur-bases as drugs to animals 

 has not led to definite results in this direction, but in 

 experiments with nuclein or nucleo-proteids the results in 

 the case of most observers have been in the direction of 

 a proportionate increase in the uric acid out-put. In a 

 recent paper, Jerome' 2 narrates the result of an experiment 

 upon himself in which the uric acid excretion was deter- 

 mined upon different dietaries. He concludes that "the 

 daily out-put of uric acid is so easily, so surely and so 

 largely controlled by the use of suitable articles of diet as 

 to make it highly probable that the variations in the 

 amount of uric acid excreted in health from day to day are 



1 Horbaczewski : Monatsh. f. Chew., Bd. 10, S. 624, 1889 ; and Ztschr* 

 f. Physiol. Chem., Bd. 18, S. 341, 1893. 



2 Jerome: Jour, of Physiol., vol. 22, p. 146, 1897. (This paper 

 contains an account of previous work upon this subject.) 



