892 
PLANTS IN SLEEPING ROOxMS. 
cles after prolonged immersion in the colouring fluid showed 
staining, but that staining was invariably uniform from 
centre to circumference, proving conclusively the absence of 
a nucleus so far as carmine staining can prove anything. 
On these observations he bases a strong suspicion that the 
alcohol and corrosive sublimate used are responsible for the 
appearance of nuclei in corpuscles treated by Bdttcher’s 
method. This suspicion receives support from recent dis¬ 
coveries as to the structure of nuclei. In the July number 
of the Quarterly Journal of Microscopical Science , Dr. Klein 
relates ai series of observations, as a result of which he affirms 
the nucleus to consist of a fibrillar network, embedded in 
which is a ground substance; that this intranuclear net¬ 
work is continuous with a similar intracellular network; that 
nucleoli are merely the thickenings and shrivellings of these 
fibrils. The natural shrivelling effect of alcohol might readily 
produce a pseudo-nucleus in a blood-corpuscle from conden¬ 
sation of this intracellular network. —Journal of the Royal 
Microscopical Society. 
PLANTS IN SLEEPING ROOMS. 
Professor Bentley, in his recent lecture, “The Life 
of the Plant,” says there exists a w idely spread notion that 
plants when grown in rooms where there is but little ventila¬ 
tion, and, hence, especially in our sleeping apartments, have 
an injurious influence upon the contained air. This idea has 
arisen from a knowledge of the fact that plants, as already 
noticed, are always evolving a small amount of carbonic 
acid, and hence, when not exposed to solar light, wffien 
evolution of oxygen is also taking place, this deteriorating in¬ 
fluence on the atmosphere is that alone which is going on. 
But the amount of carbonic acid w hich is then given off by 
plants is so extremely small that it can have no sensible effect 
upon the atmosphere in which they are placed. It might 
readily be shown that it w ould require some thousands of 
plants, in this w r ay, to vitiate the air of a room to anything 
like the extent of a single animal, and that, therefore, the idea 
of a few' plants rendering the air of close rooms unwholesome 
by this action is altogether erroneous. 
While carbonic acid gas has thus been proved to be essen¬ 
tial to plants, nearly all other gases are more or less injurious 
to them. Hence we have at once an explanation of the 
reason why plants growing in the air of large towns, and more 
