1899] BRIEFER ARTICLES 315 
made no attempt to describe the mechanism and place of the sexual 
act, that is, the fusion of sexual nuclei. Schmitz, however, formulated 
explicit theories as the result of his studies, and gave to the world an 
explanation, or rather, a set of explanations, describing several types 
of morphological structure and a variety of physiological conditions 
concerned with the sexual organs. His views have been dominant 
until very recently. 
The most striking features of Oltmanns’ contribution is the manner 
in which he has swung away from the complex and frequently obscure 
theorizing of Schmitz, and presented an explanation comparatively 
simple in the demands it makes upon the facts, and perfectly in accord 
with the stand that biology takes as to the essential conditions and 
characteristics of the sexual act. To appreciate thoroughly Oltmanns’ 
Views it is necessary that one should know the peculiarities of the the- 
es of Schmitz, and wherein they departed so radically from certain 
seneral conclusions of biological science. 
: It is not easy to discuss so complex a subject in a few words. The 
dificulties lie in the fact that the Rhodophycez present a number of 
different structural characters in the sexual apparatus, making possible 
* lanety of physiological conditions. Thus there is scarcely one genus 
" Is ey like another as to the detailed morphology of the sexual 
sans, and, indeed, species of the same genus often differ among 
themselves, 
When one considers how little precise cytological work has been 
: . 
a os group and how much lies before the investigator, the pos- 
fee] 
, 
Many types, are stimulated by this plenonienon to produce carpo- 
Owever, the auxiliary cells hold very various relationships to 
Q the a and these eccentricities have caused the es 
the tricho ee St cases, as for example Nemalion, the cell t et 
tions . itself develops the glomerule of spores, ne he 
Tucleus pa €n reported, according to which it appears that t ge 
QUcleys ‘i pi down the trichogyne and fuses with the spare 
™ Physio} isan region of the cell below. It seems ss . 
sical conditions during the processes of fertilization 
the trichog 
