ON FECUNDATION, MATURATION, AND FERTILISATION. 327 
ADDENDUM. 
SHortiy after the above notes were sent in to await publi- 
cation an interesting and suggestive paper by Boveri! appeared, 
which it is necessary for me here to briefly notice. 
If I understand Boveri aright, his results and mine agree 
up to the stage I have figured in fig. 3, but after that they 
differ considerably. In the stage I have drawn in fig. 6 Boveri 
finds the centrosome, not as one, or two, very minute inten- 
sively staining granules, but as a hollow vesicle swollen to such 
a size as to be separated from the radial striations by a very 
narrow “‘heller Hof.” He finds no trace of any deeply-staining 
central body.. In going carefully over my preparations for a 
second time, I cannot discover the slightest reason for Boveri’s 
interpretation. The one, or two, central bodies are so clearly 
defined that I am surprised Boveri has not found them. Of 
course it is possible that, as he suggests, this body, or bodies, 
may be merely the “ Centralkorner” of the centrosome ; but if 
this is so I am at a loss to know where the real centrosome is. 
I must, however, state that in one or two preparations I have 
distinctly seen a ring round the centrosomes, e.g. fig. 6, which 
according to Boveri should be the centrosome in an earlier 
stage of swelling up than he has figured. I consider, how- 
ever, that this appearance is unimportant and may be an arte- 
fact, as in many cases where the centrosomes were very plain,— 
e.g. in figs. 3, 4, and 11,—there was no trace of it. It is, I 
think, a matter of some regret that Boveri has as yet only 
published a single figure illustrating his work. I hope, how- 
ever, I may not be construed as in any way trying to depreciate 
the accurate and valuable work of such a distinguished observer 
as Professor Boveri, who has had such a far wider experience 
in cellular morphology than myself, but in this particular case 
I cannot help thinking that his interpretation is erroneous. 
1 “Ueber das Verhalten der Centrosomen bei der Befruchtung des Seeigel- 
ries nebst allegemeinen Bemerkungen tiber Centrosomen und Verwandtes.” 
‘Verhand. der Phys.-med. Gesell. za Wiirzburg,’ N. F. Band, xxix. 
