460 REPORT OF THE CONFERENCE ON GENETICS. 
this hybridisation I next proposed to import into the large-flowering 
varieties the fire or scarlet-red of the zonals, and also to make the 
leaves capable of resisting the attack of aphides. 
Iwas not for a time successful in either of these aims, but could 
constantly detect more favourable indications in the foliage. 
At this point I should say that the hybridisation between these two 
plants presented unlooked-for difficulties, which were, in fact, only over- 
come after I had made improvements in both, following 6ut the theory 
of Herr Lindemuth, Inspector of Gardens. But even after this I was 
only successful in the crossing between these two plants when I used 
Pelargonium grandiflorum exclusively as seed-bearer (female plant). 
With the zonal pelargonium as seed parent unfortunately I never suc- 
ceeded. 
I should have expected better results if I had been able even once to 
make the zonal pelargonium the female plant. I explain to myself the 
failure of the zonal pelargonium to become the seed-bearing parent in 
the following way, but whether my theory is correct or not I do not 
know. 
Since Pelargonium grandiflorum is larger in all parts of its blossoms 
than the zonal pelargonium, its pollen grains may be too large to find 
an entrance into the pollen-tube of the zonal pelargonium, and therefore 
fertilisation becomes impossible.* 
It is a most disappointing thing that most crossings, and those 
precisely the most difficult and the ones from which the best results - 
are to be looked for, produce infertile seedlings. It is just these that 
are so important in the continuation of further fertilisation, that the 
experiment must be repeated, with, according to circumstances, either 
the female or male plant, until the desired result is obtained. I have, 
in fact, found this to be the case in obtaining the scarlet colour as the 
result of hybridisation between these two parents. I had unfortunately 
to reject, amongst the most remarkable hybrid seedlings, those which 
most distinctly exhibited the zonal strain, because they were absolutely 
infertile, and I had to snatch at those in which I could detect the smallest 
zonal trace. These were always crossed again with the scarlet zonal, 
till finally I arrived at my originally longed-for fiery-red strain,T 
‘Friedrich Engel.’ 
Now it became easier to raise a scarlet. There followed from this 
‘Andenken an Wildpark,’ and ultimately ‘C. Holzmann.’ This last 
shows a pure scarlet with a dark blotch, but unfortunately is completely 
infertile, and therefore cannot be used for further experiments in hybridisa- 
tion. This is the more unfortunate since a similar pure scarlet has 
never, up to the present time, appeared again in my seedlings. This one 
always reminded me of quite an old variety—‘ Hofgirtner Huber,’ which 
had quite a small bloom, but of a clear scarlet colour, and was also 
completely infertile; in fact, the generating organs were mostly quite 
* In the process of translation we are afraid this sentence has become confused. 
The pollen-tube proceeds from and grows out of the pollen grain, so that Herr 
Birger probably means that the tube proceeding from the grain of P. grandiflorum 
pollen may be too large to find its way through the style of the zonal. But this 
appears to us somewhat improbable.—Eprror. 
7 ‘Perle yon Halberstadt u. Fr. Engel.’ 
a 
