fon” BOTANICAL GAZETTE [May 
The colony is compared with the blastula stage of animal embryology, and has 
a pore like the blastopore. The antheridium develops in the blastula fashion 
with a “phialopore,”’ as does also the new colony, whether formed asexually or 
from the egg. The figures are very diagrammatic, but interesting and prob- 
ably accurate. No nuclear detail is attempted. The most striking feature 
of the paper is the terminology. Every structure has a technical name, even 
when y literary French would serve as well.—CHARLES J. CHAMBERLAIN. 
NOTES FOR STUDENTS 
Inheritance in maize.—CoL.ins’ has made some interesting observations 
on the progeny of an all-white ear of maize that appeared suddenly in a field 
planted with a variety known as Gorham yellow dent. Since the character 
with which he was dealing develops in the endosperm and usually shows 
complete dominance in crosses, this variation is out of the ordinary. The 
author classes it as a case of mutative reversal of dominance. To the reviewer 
such a view respecting the phenomenon seems unwise. In the descendants of 
the seeds of this ear, yellow was dominant to lack of yellow in varying degrees; 
it only remains then to explain the non-development of yellow in the original 
aberrant ear. It has been generally accepted that dominance or lack of 
dominance is only another ih of SR. the somatic shpeeraice of a 
heterozygote. It has nothing to do with ly asan 
indication of zygotic composition. The true eadieation of any individual can 
be determined only by breeding from it, for there are characters so variable 
in their dominance that the appearance of the heterozygote may be similar 
to either homozygote (AA or aa). In spite of its variability, however, 
dominance does not just happen. It has its causes. An individual AA may 
be crossed with various kinds of aa individuals and the degree of dominance be 
different in each cross, but these various manifestations are due to internal 
differences between the aa organisms. On the other hand, external conditions 
may affect the manifestation of a character either when in a heterozygous or 
when in a homozygous condition. One may assume, therefore, that dominance 
is not a phenomenon of great variability when both external and internal 
conditions of development are identical. For these reasons, the reviewer has 
a suspicion that CoLLins’ mutative reversal of dominance was nothing but 
suppressed development due to some abnormal environmental condition, 
possibly the accidental presence of some particular metallic salt in the spot 
of soil in which the plant grew. The reviewer has observed somewhat similar 
phenomena, but has never thought his own ignorance of their exact cause a 
sufficient excuse for an attack on well established theories. 
Seeds from Co..ins’ “‘albinistic” ear were planted and the progeny investi- 
gated. His results show clearly that he was dealing with the behavior of two 
7 Cottins, G. N., ssid of a maize variation. Bur. Pl. Ind. Bull. 272. pp. 
23; pl. Fi fig. 8. 1933 
