1898 | CURRENT LITERATURE 139 
THE EMBRYOGENY of Triticum has been investigated by M. Koernicke.* 
He finds the usual axial row of four mother cells in the ovule, the lowest of 
which develops the macrospore. As already well known among Graminee, 
the antipodals are most apt to develop a more or less extensive tissue, which 
the author considers to be accomplished by direct division. The chromo- 
somes were found to be usually sixteen in number in the vegetative cells of 
the inflorescence, eight in the mother cells of both microspores and macro- 
spores, and sixteen again in the oospore.—J. M. C 
Davip M. MoTTiER has recently published a paper* on the behavior of 
the nuclei in the development of the embryo sac and the phenomena of fer- 
tilization. The plants studied were Lilium Martagon, L. candidum, L. 
umbellatum, Helleborus JSoetidus, and Podophyllum peltatum, the same plants 
as those used by the author in his previous paper*> upon a related subject. 
The methods were also the same. 
At an early stage in the development of the primary nucleus of the embryo 
= aremarkable differentiation takes place in the cytoplasm. Numerous 
kinoplasmic threads appear which may form a felt around the nucleus, or 
may take the form of strands radiating from the nucleus, or may even be 
Separated from the nucleus and form a bunch in one end of the cell. Later 
these threads disappear, and the cytoplasm seems to have a uniform struc- 
_ : The spirem and segmentation stages take place just as in the author's 
description of pollen mother cells. He still regards synapsis as an artefact. 
hi a: to the only previous description of spindle formation in plants, 
wh wignard,”° who says the spindle takes its origin from two directive 
Pieres. Since Mottier declares that there are no directive spheres in pollen 
“ee formation. He finds kinoplasmic fibers variously arranged which 
ine bee nuclear cavity as the nuclear membrane disappears. some of 
spindle ry fastened to the chromosomes and soon form a multipolar 
with the on quickly becomes bipolar. The chromosomes are V-shaped, 
_. Point toward the pole. The first division in the embryo sac is hetero- 
a 438 agrees fully with that already described in pollen mother cells. 
aa division follows without a complete resting stage. : The spin 
Mottier 7. a the same as in the first division, but not so easily studied. 
Surprised to find that the segmentation of the spirem came after 
nae Verhandl. Naturhist. Ver, Preussen Rheinl. 53: 149-185. 1896. Cf. Jour. Roy. 
“Ueber be 1897, p. 553. 
leila ts as Verhalten der Kerne bei der Entwickelung des Embryosacks und die 
: _ der Befruchtung. Jahrb. wiss. bot. 31: 125-158. 1897. 
zur Kenntniss der Kerntheilung in den Pollenmutterzellen einiger 
Monokotylen. Zid. 30 : 169-204. 6 
Sci. Nat. Bot. VII, 14: 163-296. 1891. 
