yo 6 Sargant.—Recent Work on the Res 7 clts 
small and short-lived mass of tissue. Sooner or later the 
endosperm is consumed by the growing embryo. Thus the 
result of the triple fusion differs from that of a normal act 
of fertilization. The organism derived from it is not a com¬ 
plete plant. Reproductive cells formed by a true fertilizing 
act are distinguished, as we have seen, by two features. They 
give rise to an organism which (i) passes through the complete 
life-history of the species to which it belongs, and (2) combines 
in itself some characters from both parents. 
The endosperm will not stand the first test, but it has been 
found to satisfy the second. H. de Vries ( 14 ) and Correns 
( 1 , 2 ) have shown that when one variety of the Maize is 
crossed with another which differs from it in the colour or 
chemical constitution of its endosperm, the endosperm of the 
offspring commonly shows hybrid characters. Both observers 
believe that this is due to the presence of a male nucleus in 
the nuclear fusion which forms the primary endosperm-nucleus. 
This view has not escaped criticism. Nawaschin (8, p. 230) 
supports it in a thorough-going way. He considers that 
these observations have conclusively shown the triple nuclear 
fusion to be a true act of fertilization. Correns ( 1 ), followed 
by Marshall Ward ( 15 ) in a summary and criticism of the 
subject in e Nature,’ observes that another view is possible. 
The embryo itself might exercise an influence on the endo¬ 
sperm, as, for example, by the formation of an enzyme, 
Strasburger ( 11 , p. 308), though opposed to the extreme view 
that the triple fusion is in all essentials an act of fertilization, 
throws no doubt on the suggestion that the paternal characters 
in the hybrid endosperm are due to the presence of a male 
element in the nucleus from which that endosperm is derived. 
H. J. Webber ( 16 ) has lately published extended researches 
on the subject 1 . He finds that the endosperm does not 
always show hybrid characters, even though the embryo in 
the same embryo-sac may do so, and suggests that in such 
cases the second generative nucleus may not have reached the 
1 Dr. Webber’s paper is referred to in * Nature,’ vol. 62, p. 601. I quote from 
the abstract given there, as I have not seen the original. 
