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conducted an extensive series of experiments with cotton plants, intro- 
duced into Madras from the valleys of the Peruvian coast. He believes that 
if this form is cultivated on the sand-flats and drifts forming the sea-board 
to the north of Madras, the result will be commercially satisfactory. In 
his opinion the cotton should be grown with cereals, in order to enable 
the grower to pay the existing land-tax. The results adduced in support 
of his views would not, however, appear to us to warrant the conclu- 
sion at which Mr. Markham has arrived. — See Journal of Botany , No. 
xiii. p. 9. 
Influence of Smoke on Vegetation . — In a paper read before the Royal 
Society, partly on the above subject, Professor Voelcker states that he has had 
many opportunities of becoming practically conversant with the injurious 
effects which a smoky atmosphere produces on cereal crops, and that he 
regards a strong deposition of soot on wheat and other corn crops quite a 
sufficient evidence of the more or less complete injury which the crops 
must have suffered from the sulphurous acid always present in the air 
when such sooty deposits are seen on plants. The disadvantages of carrying 
on agricultural pursuits in the Potteries, or in districts where volumes of 
black smoke discharge enormous quantities of sulphurous acid into the air, 
are well known amongst the more intelligent and enterprising farmers. 
The injury done to vegetation by the smoke from copper works has been 
traced beyond a distance of four miles. Of course it might be asserted 
that the mischief was caused by the arsenical vapours ; but the latter are 
present in almost inappreciably small quantities, whilst as small an 
atmospheric per-centage of sulphurous acid as the i s injurious to 
vegetation in wet weather. The fumes arising from brick kilns may be 
said to be equally destructive of growing plants. 
Distribution of Raphides. — Professor Gulliver appears to be almost inde- 
fatigable in the pursuit of this subject. He seems even now, more than 
hitherto, to regard the presence of raphides as a sufficient character on 
which to depend in the identification of certain plants, and refutes the 
objections of his opponents by stating that the existence or non-existence 
of crystals in the soil does not appear to influence the plant, to any great 
extent, in regard to its possession of raphides. In speaking of the liliacese, 
some of which do, and others of which do not, present raphides, he observes: 
“ Such an irregular distribution of raphides in the members of one order 
might lead us to suppose that the fact must be connected either with 
seasons, climate, or soil, which I believe is not entirely the case ; because in 
some (though not all) of the species mentioned, the constancy of the 
results was verified under many such conditions. Several of the plants 
were examined more than once from various localities, and during different 
seasons and years ; while Allium ursinum and Ornithogalum umbellatum 
were particularly made the subjects of repeated and protracted observa- 
tions, and always with the same results of no raphides in the former, and 
an abundance of them in the latter species.” In support of Professor 
Gulliver’s view, it may also be mentioned, that such plants as the willow- 
herbs, which are essentially raphidiferous, may always be found with an 
abundance of raphides. The onion has formerly been given as an illus- 
tration of a raphidiferous plant, but Professor Gulliver has shown that 
