42 BOTANICAL GAZETTE [JULY 
Farmer (11), however, failed to find centrosomes in Lilium. At 
the same time Strasburger (35), directing a remarkable group of 
investigators, attacked the problem in all the principal groups of 
plants. Those who studied thallophytes found centrosomes, 
but those who studied pteridophytes and spermatophytes not 
only found no centrosomes, but, in tracing the origin of the 
multipolar spindle, they found conditions which seemed to pre- 
clude any such bodies. Just as the discovery of centrosomes 
was followed by confirmatory accounts, the multipolar spindle 
and the non-existence of centrosomes in the vascular plants 
received immediate confirmation. Guignard, Schaffner, and others 
still continued to find centrosomes in flowering plants, although 
these bodies, as represented in the figures, became noticeably less 
conspicuous than in earlier accounts. In Guignard’s (15) recent 
studies of fertilization no centrosomes are represented in the 
figures, and no reference to any such structures is made in the 
text, even during the stage at which the famous ‘“quadrille of 
the centers’ was formerly (14) described. The fact that the 
great majority of cytologists, with the most approved technique 
and provided with apochromatic immersion lenses, fail to find 
centrosomes in flowering plants, added to the fact that the mode 
of spindle-formation both in reproductive and in vegetative cells, 
does not require the participation of a centrosome, makes the 
evidence overwhelming that the centrosome, as an organ of 
division, does not exist in this group. 
In regard to the pteridophytes, the evidence is similar, but not 
nearly so extensive. The blepharoplasts of pteridophytes and 
gymnosperms will be considered later. 
In the mosses the centrosome problem has received no serious 
attention, doubtless on account of the small size of their nuclei. 
Whether there is even a blepharoplast or not still remains to be 
determined. 
In the liverworts, no centrosome is found at any stage in the 
life-history. However, in Pellia and Conocephalus, and perhaps 
in all forms with such extensive intrasporal development of the 
gametophyte, a centrosphere appears during the early divisions 
in the germinating spore, but even in these few divisions the 
nce IO te 
