1905] CURRENT LITERATURE 237 
is inclined to regard sensitiveness to gravitation far greater than hitherto supposed, 
even as much as to light. It is not at present considered possible to determine 
the time required for an organ to recover from stimulation, since the autotropic 
straightening merely indicates expiration of reaction. Other important con- 
clusions are stated in the abstract mentioned.—RaymonD H. Ponp. 
NUCLEAR DIVISION in Fritillaria imperialis has been studied by SIJPKENS,*? 
who uses a somewhat novel method. Material is fixed in Flemming’s stronger 
solution for three weeks, after which it is thoroughly washed in water and run up 
to 96 per cent. alcohol. A piece of parietal endosperm with its nuclei is now 
brought into 6 per cent. celloidin, where it is kept an hour or so longer, care being 
taken not to let the celloidin become hard. With a pipette the piece with some 
celloidin is taken up and placed upon a cover glass where the celloidin flows out, 
forming a delicate film, which in a few minutes becomes rather tough. The film 
Is moistened with 96 per cent. alcohol until it is easily separated from the cover. 
Stain in gentian violet, clear in origanum oil for two hours, imbed in paraffin, and 
cut sections about 2u in thickness; then stain again in gentian violet. 
Another method was also used. A piece of the parietal endosperm was 
brought into a drop of 50 per cent. chromic acid, which soon dissolves the proto- 
plasm away from the nuclei. The nuclear membrane itself dissolves soon after, 
leaving only the chromatic network, which is washed in water and then stained 
with gentian violet. 
From a study of such preparations S1jpKINs concludes that the reticulum of 
resting nucleus is an anastomosing network with thick, irregular knots. 
— en linin thread, with chromatin granules, but the network is a homog- 
eure. The spindle arises inside the nucleus from protoplasm which 
Sema into the nuclear cavity after the dissolution of the nuclear membrane. 
nar Teads reaching from pole to pole are formed first, the mantle fibers appear- 
§ fater.—C. J. CHAMBERLAIN. 
ot _ bungering” for priority, FiscHER™® shows wherein the theory of 
n denden ’ substances, recently presented by Loew, agrees closely with 
- view earlier expressed. Since neither Lorw nor the author have 
hice. ten _ more than enough to make the theory a rational hypothesis, the 
Writers “tt a t point to notice here is that the speculations of two independent 
kinds of ea theory. The author’s analysis is closer in that three 
Presence determ} substance are distinguished, namely: Formstojje, whose 
relative i. the habit or architecture of the plant; Reizstoffe, whose 
| induces a tendency to reproduce at the expense of vegetation or 
vie Versa. * b a 
Se eae With Sacus, Formstofje and Reizstoffe were identical; while accord- 
7 SI . : ; 
Bot. N JPKENS, B., Die Kernteilung bei Fritillaria imperialis. Recueil des travaux. 
ie ho. 2. (repaged) pp. 58. pls. 4-6. 
: ; 
Ps “hing Huco, Ueber die Bliitenbildung in ihrer Abhiangigkeit vom Licht und 
enbildenden Substanzen. Flora 94: 478-490. 1905. 
