76 BOTANICAL GAZETTE [JULY 
The stimulus to this development is quite other than that for the hair-tendrils. 
The latter, according to the author, have not been discovered heretofore in any 
seed plant.—C. R. B 
Phylogeny of the embryo -sac and double fertilization.— PoRSCH *' attempts to 
explain the usual eight-nucleate embryo sac of the angiosperms as an extreme 
reduction from the gymnosperm type, consisting of two reduced archegonia, 
the egg apparatus and the upper polar nucleus representing one archegonium, 
and the three antipodals with the lower polar nucleus representing the other. 
The egg apparatus is regarded as made up of an egg, two neck cells (the synergids), 
and a ventral canal cell (the upper polar nucleus). The antipodal complex is 
interpreted in the same way. Then double fertilization might be an attempt to 
fertilize both archegonia. 
While a combination of all the features presented by gymnosperm and angio- 
sperm gametophytes can be arranged in such a sequence, the reviewer does not 
believe that there is anything phylogenetic in it. Though the angiosperm 
embryo sac has doubtless come through stages in which there was a tissue with 
archegonia, we do not believe that any part of the archegonium, except the egg 
itself, has been retained—Cuar.es J. CHAMBERLAIN. 
Chemotaxis of Lycopodium sperms.—BRUCHMANN’s discovery that the sperms 
of Lycopodium are sensitive to citric acid and its salts is a disturbing factor im 
SHIBATA’s generalization that the chemotactic sensitiveness of the three great 
pteridophyte lines toward malic acid approves the theory of their monophyletic 
origin. Yet BRUCHMANN, apparently not sensing the humor of this idea, gravely 
softens the blow by suggesting that this aberrant behavior of the Lycopodium 
sperms does not place the lycopods outside this line of descent, but is to be 
explained by the saprophytic character of the odd gametophyte!?? He shows 
that malic acid is not responded to, and that saccharose, glucose, lactose, albumin 
and other proteins, acetic, oxalic, formic, and butyric acids are likewise ineffective. 
But to ee acid 1:1,000,000, and to its — salts in 1:100,000, the sperms 
ly, the reaction b t 1: 1000 and 1: 100 respecte 
Acids sid alkalies proved repulsive, as as in the case of other sperms. The Webe 
law was found to be valid, with the ratio 1: 30-40.—C. R. B 
Geotropic perception.—_NEwcomBE, after criticizing again es weakness of the 
experiments for the localization of geoperception, has used the old decapitation 
method for demonstrating that in some species as much as 4 or 5™™ ol the 
tip is capable of perceiving the gravity stimulus.23 He is unable to relate the 
, OTTO, Versuch einer phylogenetischen Erklarung des Embryosackes 
und der doppelten Befruchtung der Angiospermen. Vortrag gehalten auf der 7% 
Versammlung deutscher Nitesicechas uot Aertzte in Dresden am 16. Sept. 1997- pp» 
I-49. 14 text figures, 
22 BrucHMANN, H., Von der Chemotaxis der Lycopodium-Spermatozoiden- 
Flora 99: 193-202. pa 
, Gravitation m Cc Aa, at root Beih- 1 
(= 
Bot. Centralbl, rola pl. 3. figs. 6. mak 
