668 
SHORTER ARTICLES. 
NOTES ON THE DEVELOPMENT OF THE POLLEN 
TUBE AND FERTILIZATION IN SOME 
SPECIES OF PINES. 
DURING the past three years, I have devoted 
considerable time, under the direction of Pro- 
fessor George F. Atkinson, to a study of fer- 
tilization and related phenomena in certain 
species of pines. A preliminary paper was 
read before the Botanical Society of America at 
its Boston meeting, August, 1898. In June, 
1900, a more complete report of the work was 
given in two papers, one of which was pre- 
sented before the society named above at its 
meeting in New York City, and the other be- 
fore the American Association for the Advance- 
ment of Science, which Association also met in 
New York City. 
It has been found that the generative cell 
appears, as a rule, during the first summer 
rather than shortly before fertilization, as de- 
scribed by other investigators. This cell does 
not divide while in its place within the pollen 
grain, as stated by previous writers, but passes 
into the pollen tube before the sperm cells are 
formed. In the division of the generative nu- 
cleus, the spindle is monopolar in origin; it 
arises some distance below the nucleus in a 
prominent cytoplasmic condensation. From 
this denser area the protoplasm extends in a 
radial manner towards the periphery of the 
cell. The sperm nuclei are never separated by 
a cell wall, but remain surrounded by a com- 
mon mass of cytoplasm. Thetwo nuclei are of 
unequal size from the first, and the larger one 
is always in advance of the smaller one, as re- 
gards the apex of the pollen tube. 
Just prior to fertilization a cavity is formed 
in the upper part of the egg cytoplasm. It is 
believed that this cavity represents the final 
act of the egg in its preparation for the recep- 
tion of the sperm cell and other contents of the 
pollen tube. There is no evidence that it re- 
sults from the presence, within the egg, of the 
elements from the pollen tube, as reported by 
certain writers. The sperm nucleus does not 
increase in size after its entrance into the egg, 
but remains much smaller than the nucleus of 
odsphere. The sexual nuclei come to lie side 
by side but do not fuse ; both nuclei can still be 
SCIENCE. 
(N.S. Von. XIII. No. 330. 
identified, even after the membrane of each 
has entirely disappeared. Two chromatic 
groups are clearly distinguished up to the nu- 
clear plate stage. 
In the division of the two segmentation nu- 
clei, the chromatin of each nucleus forms two 
distinct spirems, which doubtless represent the 
separated-out paternal and maternal chromatic 
substance. At the time of this second division 
within the odsphere, the smaller sperm nu- 
cleus, which still lies in the upper part of the 
egg, frequently gives rise to a mitotic figure of 
more or less definiteness. 
Only a few of the results which have been 
obtained are noted above. Papers giving the 
details of this research, with discussion and 
plates, have been sent to the publishers and 
will appear shortly. 
MARGARET C. FERGUSON. 
BoTANICAL DEPT., CORNELL UNIVERSITY. 
NOTES ON ENTOMOLOGY. 
WITH the December (1900) number the Ento- 
mologische Nachrichten, long edited by Dr. F. 
Karsch, closes its career. In its place will be 
issued a monthly index of entomological publi- 
cations, called Entomologische Litteraturblitter. 
M. Auc. LAMEERE, in a recent proposed clas- 
sification * of the Coleoptera, divides the order, 
according to the variation of the median vein of 
the hind wings, into three suborders ; viz., Can- 
tharidiformes, Staphyliniformes and Carabi- 
formes; the last is equal to the Caraboidea of 
Ganglebauer. The second suborder equals the 
Staphylinoidea of that author with the impor- 
tant addition of the Pulicide. 
M. Lameere’s idea that the fleas are Coleop- 
terous insects is certainly novel, and is based 
on a supposed affinity with Platypsyllus, the 
well-known parasite of the beaver. The Can- 
tharidiformes contains all the other families. 
M. Lameere makes a list of the characters 
that (according to him) must have been pos- 
sessed by the ancestor of Coleoptera; these 
characters indicate a Neuropterous insect of the 
group of Plannipennia. The most primitive 
Coleoptera he finds in the family Lymexylide. 
*Notes pour la classification des Coléoptéres. 
Ann. Soc. Ent. Belg., 1900, pp. 355-357. 
