472 BOTANICAL GAZETTE [JUNE 
Effects of carbon monoxid on plants. —SEELANDER*4 concludes from numerous — 
experiments that carbon monoxid is to be regarded in general as a plant poison and 
should be classed as an anaesthetic weaker than chloroform. It exerts injurious 
effects upon seedlings of Lupinus albus and upon germinating spores of Mucor 
stolonijer, M. Mucedo, Penicillium glaucum, Aspergillus niger, and Botrytis 
cinerea. ‘The injurious effect upon seedlings of Lupinus albus is shown by an 
inhibition in rate of growth of the rootlets, which effect is observable with con- 
centrations varying from 75 per cent to o.5 per cent. Injurious after-effects are 
to be observed only when the higher concentrations and long exposures are used. 
Seedlings exposed to the gas show an increased resistance to drying. The spores 
of the fungi named, germinated on nutrient gelatin in the presence of carbon 
monoxid, showed delay in germination, and an inhibition in rate of growth of the 
hyphae, which, especially in the higher concentrations, were irregularly bent and 
swollen. The minimum concentration necessary to produce the observed results 
was 1 per cent. The amount of respiration in tubers of Solanum tuberosum, 
bulbs of Allium Cepa, petals of roses and dahlias, and swollen seeds of Pisum 
sativum and Brassica Napus was little affected by a mixture of 79 per cent carbon 
monoxid and 21 per cent oxygen. The streaming of the protoplasm in Nitella 
and in the hairs of various plants, and the ciliary. movements of Chlamydomonas 
and Haematococcus are not affected by several hours’ exposure to the gas.— 
R. C. Rose. 
Permeability.—RvuHLAND has already published a papers showing that 
many dyes highly soluble in lipoids do not enter the protoplasm, while many not 
soluble in lipoids do. He now offers still more evidence?® against OVERTON’S 
lipoid theory of permeability, especially directing attention to the nature of the 
water solutions formed by the various dyes as shown by the ultramicroscope. 
finds that many of the dyes, the water solutions of which are of a colloidal nature, 
readily enter the protoplasm; methylorange is an example. Others (wollviolletts 
and erioglaucin), highly soluble in lipoids and forming true solutions in water, do 
not enter protoplasm. 
R ND also offers evidence?? against the NATHANSOHN and MEUvRER’S 
ion permeability hypothesis, which holds that in the exchange of electrolytes 
between cells and a bathing solution, an electro-chemical balance is maintained. 
He points out that OstwaLp’s hypothesis, with which this agrees, has long since 
become untenable from the physical standpoint. He also believes that the 
large amount of Ca++ and Mg++ given off in NATHANSOHN’s experiments in 
24 SEELANDER, Kart, Untersuchungen iiber die Wirkung des Kohlenoxyds auf 
Pflanzen. Beih. Bot. Centralbl. 241:357-393. 19009. 
25 Rev. Bot. GAZETTE 47:342. 1909. 
6 RUHL , W., Die Bedeutung der Kolloidalnatur wasseriger Farnstofflosung 
fiir ihr ein in lebende Zellen. Ber. Deutsch. Bot. Gesell. 26:772-782- 1999- 
27 , Zur Frage der Ionenpermeabilitat. Zeit. fiir Bot. 1:747-762- 1999- 
