tort] MACDOUGAL—OVARIAL TREATMENTS 249 
self-fertilization. The derivative is thus seen to differ from the 
parent in every stage of ontogeny and reproduction. The differ- 
ences in question have been maintained through five generations 
and four sets of climatic and soil conditions. 
A few hybridizations of derivatives with the parent have been 
made, with the result that the cross is found to be intermediate, 
being more vigorous and showing greater leaf-development than 
either parent, features which are also displayed in the second 
generation. The entire set of structural and physiological differ- 
ences, together with the results of the cross with the parent, points 
to the conclusion that the derivative is a genotype different from 
that of the parental form, to which, of course, it stands most 
closely allied, but with which it does not intergrade. 
The successes with these two forms inspired an extended range 
of experiments with a number of species of widely diversified mor- 
phological type, principally characteristic of the arid regions, 
from 1906 to the present time. Among these were included 
Eschscholizia, Argemone, Physalis, Covillea, Carnegiea, Mentzelia, 
Opuntia, Anemone, Amsinckia, Pentstemon, Echinocereus, Echino- 
cactus, Sphaeralcea, Nicotiana, Fouqueria, Solanum, Kallstroemia, 
Mimulus, Phytolacca, and Brodiaea. In addition, diligent watch 
has been kept for ovaries in which the stings of insects made 
at an early stage have resulted in serious malformations, with the 
view of testing probable action upon ovules contained. Only 
one set of seeds has been secured in this manner so far, and no 
deviations from the normal were found in the progeny arising 
from them. 
In 1910 some new methods of treatment were tested, by which 
Vapors of various substances, including bromine, were allowed to 
act upon inclosed inflorescences with eggs and ovules in various 
Stages of development.’ The fatalities were large, but several 
Progenies from this treatment are now under observation. Prac- 
tically all plants were grown as they had become established natu- 
rally, and no effort was made to secure pollination except in one 
or two instances in Pentstemon. The proportion of losses from 
Various causes was large in all cases. Operations were fairly suc- 
cessful in Pentstemon, but the stalks bearing ripening capsules were 
