1910] CURRENT. LITERATURE 395 
directly surrounded by the cytoplasm. The nucleolus then gradually assumes a 
rounded form, in which are seen 14 deeply stained tetrads that differentiate later 
into 28 chromosomes. The chromosomes become united in pairs and 14 bivalent 
chromosomes are established. The spindle is at first multipolar, but gradually 
becomes bipolar. The daughter chromosomes grouped at the poles, after the 
first division, again take the form of nucleoli in the daughter nuclei. In the 
second division 14 chromosomes are clearly distinguishable in the polar view 
of the equatorial plate. Consequently in Spirogyra jugalis 14 is the haploid 
number of chromosomes and 28 the diploid number.—Suic£o YAMANOUCHI. 
Oxidizing enzymes.—EvLER and Bottn3s have published a third paper on 
oxidizing enzymes. They have developed a method for the quantitative deter- 
mination of peroxidase. They have also devised methods for the purification of 
the peroxidase of the horseradish, which gives a far superior product to that 
obtained by BacH and CuHopat. The most highly purified product showed 
10.4 per cent of nitrogen and 2.5 per cent of ash. Contrary to the belief of 
many, the action of this substance cannot be attributed to the trivalent iron and 
chinons it contains, but it is a true enzyme. They believe the peroxidases of 
various plants are not identical. 
The oxidase of Rhus vernicifera was purified and compared with the oxidase 
of Medicago, which they have already studied in great detail.3° The latter they 
have shown to be a mixture of calcium salts of various oxy-acids and it is 
not destroyed by boiling in water. The former contains nitrogen and is very 
Sensitive to heat. Contrary to the contention of many, they find that the action 
of Rhus oxydase cannot be attributed to the joint action of contained manganese 
and hydroxyl, for it is equally effective in slightly acid, neutral, and slightly basic 
solutions. 
These investigators, through their excellent chemical training, are making 
valuable contributions in this important field of plant physiology —Wm. Crocker. 
The giant form of Primula sinensis.—GrrGorYS’ has examined the giant 
form of Primula sinensis, thinking it might have the tetraploid number of chromo- 
somes, as Miss Lurz and the reviewer found to be the case in Ocnothera gigas. 
A doubling, however, does not occur, the numbers being 12 and 24, as in the 
ordinary form of Primula sinensis. It should be said that this giant Primula 
differs from the ordinary form in practically no respect except the larger size of 
its organs, while in O. gigas many of the characters have been sharply modified 
from those of O. Lamarckiana. While Grecory finds the number of the chromo- 
somes unchanged, he believes that the chromosomes are larger in the giant form, 
35 EULER, H., np BoLtn, Ivan, Zur Kenntnis biologisch wichtiger Oxydationen. 
Ill. Zeit. Physiol. Chemie foe 1900. 
3° Ibid. 61:1~15. 1 
37 GREGORY, R. . ae on the histology of the giant and — forms of 
Primula sinensis. pe Cambridge Phil. Soc. 153:239-246. pl. I 
