1895. ] Anatomical and Physiological Researches. 327 
On the other hand, as has been said, Strasburger (16) de- 
nies the existence of peripheral fibres in the best-studied 
plants. Maintaining justly that the splitting of the chrom- 
osomes is an active, vital phenomenon, he holds that 
the movement of the daughter chromosomes to the poles is 
equally so. He considers the spindle fibres to be the guiding 
paths along which the chromosomes move, since he and 
Guignard have found a close correspondence in number be- 
tween these fibres and the chromosomes. And he believes 
their motion to take place in response to some sort of attrac- 
tion exerted by the centrosomes. Yet, since all radiations 
from the centrosomes are so faintly visible in plant-cells 
treated by the best known methods, Flemming’s suggestion 
(6) is worthy of consideration, when he hints that an im- 
proved technique may bring out the peripheral fibres in these 
cells, also. 
Of the details of karyokinesis in most of the Thallophyta 
we know very little, and most of the accounts we possess 
contain details so at variance with what we know of other 
groups, that they must be regarded as requiring confirma- 
tion. This seems especially true of the accounts of the cen- 
trosomes in these plants which have been published. 
Concerning the process of cell-fusion, which constitutes the 
essential feature of fertilization, there have been no very re- 
cent advances on the vegetable side; but it should be noted 
that recent studies of some American zoologists (19) tend 
strongly to discredit the supposed fusion in pairs or ‘‘quadrille” 
of male with female centrosomes. The centrosomes of the fer- 
tilized egg are said to be furnished sometimes by one, and 
sometimes by the other sexual element. If this be true for 
animals, a similar condition may be expected among plants 
also; but, until Guignard’s observations of the quadrille in 
Lilium Martagon are proved erroneous, there is no ground 
for doubting their accuracy. 
Since the present status of our knowledge of the facts con- 
cerning the reduction of the number of the chromosomes in 
the nuclei of the gametophyte, and of their significance so far 
as plants are concerned, has lately been sketched in this 
journal (20: 23), in an abstract of Strasburger’s last paper, it 
will not be profitable to discuss that most interesting cyto- 
logical phenomenon here.—J. E. HUMPHREY, 
