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“REPORT OF THE BOTANIST. ie OEe 
Prof. James Troop, Purdue University, La Fayette, Ind.: 
In regard to the immediate effect of cross-fertilization upon the fruit, I have tried 
the experiment here only on strawberries. Two years agolI tried it on several 
. varieties, among them Crescent fertilized by Sharpless. I thought then that the 
sharp acid flavor of the Crescent was considerably toned down. This year my students ~ 
tried the same thing, using Crescent for the female and Sharpless pollen, but we 
could not discover any change whatever in the flavor, size, or color. 
While at Lansing, about 1881, I crossed Northern Spy and Golden Russet apples, 
crossing both ways, but the Spys were Spys, and the Russets remained the same as 
those on the rest of the tree. 
I would hesitate to give an opinion either way until I have made further tests. 
Hiram Sibley & Co., Chicago, Ill. (F. A. Warner): 
As far as we have learned from information from our best growers here cross- 
fertilization does not appear during the first year. 
The writer has known it in the case of corn not to appear in any marked degree 
until the second year, and with a certain knowledge that the cross was made during 
the year previous, as the planting of the seed the second year was too distant to 
have cross-fertilization occur. 
° CONCLUSION. 
Considering all the testimony given above the writer is disposed 
to think that the evidence is still insufficient to show that there is an 
observable effect of a cross upon the ovary or fruit the first year, ex- 
cept in Indian corn, in which case his own observation will not permit 
him to doubt. It seems most reasonable to suppose that ordinary 
cases of apparent cross, observed where different varieties are grown 
together, are due to admixture of a previous year. It is admitted, 
however, that there are observations which can not be explained in 
this way. The occasional variations in the appearance of apples and 
other fruits, which have been supposed to indicate an immediate in- 
fluence of pollen, have not been proved to be due to that cause. The 
argument from seedless fruits, which is sometimes made, seems in- 
conclusive, for it has not been shown that fertilization is necessary 
to their production, though in numbers of other cases it has been 
proved that without fertilization no fruit matures. Even if true 
that the ovary, or even a larger portion of the plant, may be caused. 
to develop by pollen without the intervention of the ovules, it re- 
quires better evidence than is yet offered to show that an immediate 
change in its character will result from the use of pollen of a different 
variety. 
SUGGESTIONS FOR FUTURE EXPERIMENTS. 
For those who may-wish to experiment further on this subject the 
‘ following suggestions are appended: 
(1) Select varieties which you have reason to believe will readily 
cross. 
(2) Select such as by their difference in form or color will readily 
show the effect of a cross if there be one. 
__ (3) Use every precaution to prevent self-fertilization. To this end 
the selection, where practicable, of plants having separate sexes is 
desirable. 
(4) For the same reason cover the crossed flowers for some time 
before and after fertilization with muslin or paper sacks, and exer- 
¢ise great care in applying the pollen. , 
(5) Mark plainly and securely the flowers experimented upon that 
there may beno mistake inthe identity of the specimens when mature. 
