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of the abnormal pollengrains in the uppermost flowers of the racemes 
of Charles Dickens (1°) and Général Pélissier (1° and 2°) might be 
an argument in favour of the fact that under feeding is the cause, 
as the uppermost flowers are always in a far worse condition than 
the undermost of the raceme. However, what [ have observed in 
Yellow Hammer (5° and 6°) is not in accordance with this. For here 
the wndermost flowers of the raceme are developed in the same way 
as the uppermost of Charles Dickens and Général Pélisier though 
the same rule holds good here as well, that the undermost flowers 
are in a better condition with regard to the feeding than the upper- 
most. So at any rate the causes must be considered to be of a more 
complicated nature; of which presently more. 
5’. The abnormal pollen-tubes may developed when the bud is 
still green. In other cases they do not develop until the flowering- 
time has set in. 
6°. From the descriptions given, as well as from the large tables 
not published here, we may conclude that between the aspect shown 
by normal pollen, and Némsc’s phenomenon, there is as it were a 
gradual transition, manifesting itself as follows: 
a. Normal aspect of the pollen; fertile and sterile grains are present ; 
the latter large and elliptic. 
6. Besides the large ellipsoidical pollengrains there occur smaller 
elliptic ones and others that are round or triangular. 
c. the sterile pollengrains of various shapes and sizes get the 
upper hand, which probable indicates and early dying off, partially ; 
besides these there occur large, round pollengrains, filled with 
starchgrains. 
d. Nemxc’s phenomenon complete. 
IV. On the conditions, under which Néimuc’s phenomenon may 
come to exist. 
I may here remind the reader that all the pollen-grains examined 
originated from plants which, ou the ground of the various condi- 
tions under which they had been cultivated, were classed by me in 
13 different categories, from A to M. That I owe a considerable 
part of my results to this arrangement, may appear from a glance 
at the last table. This table shows clearly, that Némxc’s phenome- 
non confined itself almost exclusively to the categories C and B. 
Of the 20 times that this aspect was found it occured 11 times in 
C, 6 times in B and once in D, K, in: H. Besides it immediately 
struck the eye, that the pollen-aspects which showed one of the 
