nucleic acid. 
424 BUTANICAL GAZETTE [JUNE 
fuchsin-iodine-green mixture the generative nuclei of pollen 
grains stain green, and the tube nuclei red; but more recently 
(1892) he has discussed quite thoroughly the staining reactions 
of the nuclei. The nuclei of the small prothallial cells of gym- 
nosperm microspores are cyanophilous, like generative nuclei. 
The nuclei of the nucellus surrounding the embryo sac are also 
cyanophilous. His conclusion is that the cyanophilous condi- 
tion in both cases is due to poor nutrition of the nuclei, the 
amount of cytoplasm being small in proportion to the size of 
the nuclei. On the other hand, the erythrophilous condition of 
the nuclei of the embryo sac is due to abundant nutrition. As 
a further proof of the theory it is noted that the nuclei of the 
adventitious embryos which come from the nucellus of Funkia 
ovata are decidedly erythrophilous, while the nucellus to which 
they owe their food supply has cyanophilous nuclei. ; 
In division stages nuclei are cyanophilous. From anaphase 
to resting stage cytoplasm is taken into the nucleus and the 
cyanophilous condition gradually changes to the erythrophilous, 
but when a nucleus is prevented from taking nutrition from a 
large amount of cytoplasm, as is the case with generative nuclei 
of pollen grains and the nuclei of the small prothallial cells of 
gymnosperms, the reaction remains cyanophilous. It is an 
added proof, that in Ephedra the tube nucleus, which has very 
little cytoplasm about it, is cyanophilous. Strasburger claims 
that there is no essential difference between the male and female 
generative nuclei, and observation shows that within the 
oosphere spermatozoids and other male generative nuclei 
become erythrophilous, so that the sex nuclei are alike in their 
reaction to stains. Malfatti and Lilienfeld have proved that 
these reactions are dependent upon the amount of nucleic acid. 
Chromosomes during mitosis consist of nearly pure nucleic acid 
and are intensely cyanophilous ; while cytoplasm has little or 7° 
nucleic acid and is erythrophilous. There are all gradations 
between the cyanophilous and erythrophilous conditions, the 
affinity for basic anilines being in proportion to the amount of : 
