86 BOTANICAL GAZETTE [JANUARY 
the mountain las rising from partially cultivated rocky pastures near the © 
river. A belt of woodland occupies the valley slopes up to an altitude of about 
3600 feet, the sae forest consisting of Betula odorata, reaching a maximum 
shru 
association persist in the belt of alpine shrubland, which reaches a poorly 
defined upper limit (4500-4800 ft.) with the disappearance of its most persistent 
members, Salix reticulata and Betula nana. Above is a luxuriant alpine 
lichen association, affording pasture for the reindeer and dotted with a variety 
of alpine flowers. Among the notes upon the many species examined, the 
scarcity of Sphagnum even in bogs is emphasized, and the results of a study of 
the variation at different altitudes of the leaves of Betula nana, both in size 
and structure, are recorded.—Gero. D. FULLER. 
- Parthenogenesis i in Bennettites.—In 18094 LIGNIER published an account 
of the structure and affinities of Benneitites Morieri, and now, upon loo 
over his former pa gmegg he has come to the conclusion that the species 
was parthenogenetic.® The evidence is that the’ nucellar beak is not per- 
forated or disorganized in any way, but is an absolutely continuous mass of 
primary tissue, that is, not tissue arising by proliferation and filling a passage- 
way. The pollen chamber forms within the beak and extends more or less 
toward its fis but never reaches the surface, so far as the author’s preparations 
show. This is taken to prove that the observed embryos have developed in the 
absence of pollen tubes; it is recognized that they may or may not be partheno- 
genetic in the sense of arising from an unfertilized egg. It is further suggested 
that the parthenogenetic habit may have been the chief cause of the rapid 
disappearance of a group that was so flourishing during the Jurassic.—J. M.C. 
Permeability.—Czarrx* has brought together all his work on the effect 
of the surface tension of the surrounding fluid on the permeability of the 
Plasmahaut of the plant cell. Reviews” of preliminary articles have given 
the main points of this paper. Some evidence is offered that acids have their 
effect by interfering with the Plasmahaut emulsion. CzAPEK also doubts 
TRAUBE’S conception of osmosis, though his experiments offer little 
evidence against it. Many more substances were found which produced ex0s- 
mosis of the cell contents of phanerogams only when their aqueous solutions 
had a surface tension of 0.68 (or less) of that of water. The Plasmahaut of 
20 LicNiER, O., Le Benneltites Morieri (Sap. et Mar.) Lignier se reproduisait 
cer 2 parthénogénése. Bull. Soc. Bot. France 58: 224-227. 1911. 
21 CZAP , Ueber eine Methode zur Bestimmung der Oberflichenspannung 
der Pama von Pflanzenzellen. 8vo. pp. iv+86. figs. 3. Jena: Gustav Fischer. 
Tore. Ma. 
22 Bot. Gaz. 50: 234. rg1o, and 51:472. Igtl. 
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