1899] CURRENT LITERATURE 145 
double row of chromatin granules, a preparation for a second splitting, so 
that the primary chromosomes are to be regarded as quadruple. As the 
primary chromosome separates into its two parts (secondary chromosomes), 
the splitting already inaugurated by the fission of the granules begins to take 
place, but is not entirely completed, since the two chromosomes remain united 
at their extremities, thus forming a V with its apex attached to the contractile 
threads of the spindle. Each daughter nucleus receives six double (second- 
ary) chromosomes. 
Second division.—In the second division, six V-shaped chromosomes 
appear. At the point of the V there is an interruption in the linin support and 
everything favors the conclusion that these are the secondary chromosomes 
of the first division which have not lost their individuality. No longitudinal 
division takes place at this time, there being merely a distribution of the two 
parts of the V-shaped double chromosome. Thus the two divisions merely 
distribute the four parts of the primary quadruple chromosome (tetrad), which 
were already defined in the prophase of the first division. It is evident that 
there can be no qualitative reduction. 
: Miss Sargant ® both figured and described a second fission of the chroma- 
z A in Lilium Martagon, and called attention to the quadruple nature 
<ce Preaek chromosome. Guignard believes that his results agree with 
neh Se of Pallavicinia, Brauer’s of Ascaris, Meves’ of Salaman- 
a different mp with Belajeff's description of Iris, although that writer has given 
cell, An €xplanation of the origin of the chromosomes in the pollen mother 
diagrams ame review of the chromosome problem, illustrated by very clear 
The ee no means the least important part of the work. he 
of Lilium hay ied results of Nawaschin and Guignard on the fertilization 
tilization the : a confirmed by Miss Sargant," who finds that during fer- 
male ile € nucleus is applied to the female nucleus, while the second 
Polar nuclei w, applied fo both the polar nuclei. In one case, in which igs 
united them ae _ yet in contact, the much elongated “ antherozoid 
Pollen tube ie : brid . In several preparations it was noted that - 
Since both pes, Pe eiization had taken place, contained two small ree 
are ies. nuclei are already accounted for, it is suggested that 
CHAMBERLATN, y due to the division of the tube nucleus.—Cuas. J. 
toa 
Ann, Bot. 17; 187-224. 1897, 
"On th ‘ 
Pa nh * Presence of two vermiform nuclei in the fertilized embryo-sac of Lilium 
roc. Royal Soc, 65 : 163-165. 189 
