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J. IRamsbottom, 
The latter are generally larger than the former and their nuclei resemble 
in size and appearance the fusion nuclei of the hypothecium. A certain 
amount of evidence was obtained as to mitosis in both the vegetative and 
the fertile hyphae; the number of chromosomes in the first appears to 
be two, and in the latter four, and then eight. “The nuclei are, however, 
so minute that it would be unwise to attach any great importance to 
these phenomena.” In the divisions in the ascus brachymeiosis (a second 
reduction as first recorded by Fraser in Humaria rutilans) occurs. The 
first division is heterotype with four bivalent chromosomes, the second 
homotype with four monovalent chromosomes, and the third brachymeiotic 
with two chromosomes. This latter number is confirmed by the fact that 
in mitosis in the spore two chromosomes go to each pole. Neither Me 
Cubbin nor Brown found a second reduction in the ascus. 
In the Pezizineae Guilliermond (1911) has criticised the work 
of Fraser and her pupils on the divisions in the ascus. He has again 
worked at Humana rutilans , the species in which Fraser first recorded 
brachymeiosis. He had previously (1904—1905) published an account 
of the nuclear divisions in the ascus of this species, and unfortunately did 
not cut fresh material for his present study, but used his old slides. The 
nuclei of H. rutilans are very suitable for the study of these phenomena. 
Guilliermond now considers that Fraser’s account of the first two 
divisions, a heterotype followed by a homotype, according to the scheme 
formulated by Farmer and Moore for the reduction divisions in both 
animals and plants, is probably correct. He admits that he missed “plusiers 
stades” recorded by Fraser. However, he considers there is no second 
reduction. He finds there are sixteen chromosomes present in the first and 
second divisions and from a study of all his figures he thinks that in the 
third division the number of chromosomes is certainly greater than eight, 
and approaches sixteen although he could not count the number exactly because 
of their length and twisting. “Comme, d’autre part, les figures de Fraser 
ne sont pas plus démonstratives que nos préparations (et ne peuvent l’être), 
nous nous permettrons donc d’émettre des doutes très sérieux sur l’exacti¬ 
tude de l’interpretation de cet auteur et de considérer son opinion comme 
une simple théorie qui aurait besoin de trouver sa démonstration.’’ 
Guilliermond also re-examined his old slides of Peziza catinus 
and Pustularia vesiculosa, the latter being one of the species in which 
Fraser and Welsford state that brachymeiosis occurs. In P. catinus 
he finds the first two divisions favourable to Fraser’s view, but the 
number of chromosomes remains constant throughout the three divisions. 
In P. vesiculosa the chromosomes are less in number and smaller in 
size than in the other species investigated and their enumeration is much 
easier and allows of remarkable precision. He insists that there is no 
numerical reduction in the chromosomes their number being eight throu¬ 
ghout the three mitoses. 
The author also again studied Galactinia succosa but did not rely 
on his old preparations as the series was not complete. In his previous 
investigations he had thought that the divisions took place according to 
Maire’s scheme, which seemed to agreesome what with Fraser’s ideas 
concerning the significance of the third division in the ascus, but he holds 
that his latest study shows conclusively that the number of chromosomes 
