690 Sargant.—-Recent Work on the Results 
centre of the embryo-sac is clearly seen to be a fusion of 
three nuclei, not two. 
The same phenomena were observed by Nawaschin in 
Fritillaria tenella and by Guignard in other species of Lilium 
( L . pyrenaicum , &c.). Botanists were therefore presented 
almost simultaneously with two independent sets of con¬ 
cordant observations made by two observers of the first rank 
on a few closely allied species. So unlooked-for were their 
results, that evidence less irresistible than this might well 
have needed confirmation. As it was, the facts were generally 
accepted at once (Strasburger, 10 ), and became the starting- 
point for further research. This has now proceeded for over 
a year in more than one direction. 
As facts have accumulated, the question of their theoretical 
importance has become more pressing, and we have now 
several conflicting opinions on the subject. I propose in this 
paper to collect together, so far as is possible, all the work 
which has followed the original discovery, and to consider 
its bearing on the theoretical considerations involved. Such 
an attempt in these early days can have at the best no 
permanent value. But it is sometimes useful in the early 
stages of an investigation to take stock, as it were, of our 
assets of knowledge. This is more particularly the case 
when the subject is of general interest, and the work done in 
it is scattered through a number of memoirs by specialists. 
Much of this work has already been collected by Stras¬ 
burger (11) in his recent important paper in the Botanische 
Zeitung, to which I shall have occasion to refer again. 
Four distinct questions were suggested by the discovery 
of c double fertilization 1 .’ They may be briefly stated as 
follows:— 
1. Is the phenomenon of double fertilization general among 
Angiosperms, or to be considered as peculiar to a few species ? 
3. Does the twisted (vermiform) shape of both generative 
nuclei in Lilium indicate that they have an independent power 
1 The expression ‘ double fertilization ’ is used for convenience throughout this 
paper, and is not intended to imply any view as to the nature of the conjugation. 
