DR. DENNY ON RELATIVE INFLUENCE OF PARENTAGE. 19 
by the father. The recorded results of my crossings indicate an 
immense preponderance of influence over the progeny on the part 
of the father in all respects — in colour and in form, in the quality, 
in size and substance of the flower, as well as in the production 
of variegation of the foliage, and in the habit and constitution of 
the plant also, provided the plants employed are of equal strength. 
I wish to be distinct upon this point of relative strength of the 
parents, because it seems to me that upon the equality or the 
preponderance of strength on either side very much hinges as 
regards the results we obtain from our crossings, for power of con- 
stitution exerts most unmistakable influence, and where it prepon- 
derates on the part of the seed-parent it will modify the otherwise 
prepotent influence of the pollen-parent. This modifying influence 
manifests itself most as regards the habit and foliage of the plant, 
and next as regards the form and substance of the flower, and 
lastly as regards the production of a blend in the colour of the 
flower. 
To illustrate what I mean, if the pollen of a flower of Pelar- 
gonium, of brilliant and decided colour, but of bad form and 
substance, belonging to a plant of weakly constitution, be applied 
to the stigma of a finely-formed, thick-petalled flower of a plant 
possessing a vigorous constitution, some few of their progeny 
will be improved in the form and substance of the flowers and 
habit of plant, with, perhaps, some blend in the colour, showing 
that the preponderance of vigour in the seed-parent had exerted a 
certain amount of influence ; but even under these circumstances 
much the greater proportion of the progeny would either resemble 
the father in all respects, or show reversion towards former proge- 
nitors or an original type. 
I will quote a case or two in point from my note-book. During the 
summer of 1869 1 raised about 140 seedlings from crossings between 
Lord Derby and Leonidas. In about half of these Lord Derby 
was the pollen and Leonidas the seed parent, and half resulted 
from crosses effected the reverse way. The flower of Lord Derby 
possessed the fine qualities, both as regards form of petal and 
smoothness of texture, but was wanting in depth and brilliancy of 
colour, and also in substance ; and the plant was deficient in vigour 
of constitution as compared with Leonidas. The flower of Leonidas 
was much inferior as regards form and quality, but of greater sub- 
stance and brilliancy of colour, as well as larger than that of Lord 
Derby, and the plant possessed a vigorous constitution. 
These seedlings flowered during the spring and summer of 
c 2 
