April S, 1888. J 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER, 
285 
where they are well exposed to the light and air. This may be in a 
pit or greenhouse, or if the weather is genial in April in a cool frame. 
When the growths become so long as to be inclined to fall over they 
should be supported by a few tall twigs, and supplied with plenty of 
water at the roots. Insects will never trouble them, and as soon as they 
gain a height of 18 inches they will begin to show flower, and then the 
best position is the greenhouse or conservatory, as the soft green of 
the foliage, the bright hues of the flowers, and their delicious fragrance 
gain them general favour. If the flowers are allowed to form seed the 
supply will soon cease, but if they are cut before they wither a long 
succession will be produced.—A Kitchen Gardener. 
THE EUCHARIS BULB MITE. 
For the past three years we have had a few bulbs of Eucharis decay 
through the autumn and winter months, and in each instance I have 
found this little insect on the decayed bulbs and in the soil adhering 
thereto. It appears to me the mite attacks the bulbs when the soil 
in which they are growing in remains wet for several days together. I 
think an average temperature of 60° during the dull months of the year 
is anything but a good one for the Eucharis. This is the temperature our 
plants are in during the period named above. To prevent the soil 
becoming too wet we have to water the plants very carefully, and by 
adhering strictly to this, I think we prevent the insects attacking more 
Fig. ss. 
.A.—Eucharis bulb, natural size, showing mites. 
B. -Mite enlarged fifty diameters; the male and female are the same size, they differ a 
1 ttie underneath. Body colourless, legs very pale rose, with two brown spots on 
body. 
C. -Hypopial form, enlarged fifty diameters. 
D. —Suckers from underneath ditto, enlarged 150 diameters. 
of our plants than they do at present. By what I have noticed for some 
time, I am of opinion that drought is detrimental to the mite. I do not 
wish anyone to think that we keep our Bucharises on the verge of flag¬ 
ging to prevent the bulbs being attacked by the mite. Our aim is to 
keep the soil in which these plants are growing neither wet nor dry. 
Nothing will prevent the roots of the Eucharis decaying if the soil is 
allowed to become dust dry, and is then saturaced directly after. With 
these notes I am forwarding a few decayed bulbs, with the insects on 
them, for the Editor’s inspection.—E. 
RHIZOGLYPHUS ROBISI. 
Apropos of the Eucharis mite and its brethren of that group, I 
have to remark, first that they furnish one of the most perplexing 
problems in insect life, and their study is quite a specialty, to which 
some naturalists, chiefly continental, have given a large amount of time 
with only small positive result. The creatures are found to occur in 
two forms, so peculiarly distinct that it is thought by some the one is a 
parasite by which the other is attacked and devoured; while others 
argue that the insect is all one 8,,ecics throughout, but undergoes a 
curious translormation. On the whole, our latest evidence favours the 
latter view, but there is this complexity, that though for some time it 
was supposed the hypopoid harder-skinned form was the final out¬ 
come of the Rhizoglyphus, instances have been discovered where it was 
just the reverse, the Hypopus becoming a Rhizoglyphus. The most 
feasible conjecture is that under certain atmospheric conditions the- 
changes are modified by Nature, and the supposed hardier Hypopus type 
appears when the Rhizoglyphus would be liable to extinction. All this 
is exceeding curious, but probably not interesting to the majority of 
gardeners. We are still in the dark on the important point, how these 
insects, seemingly very sluggish, manage to transfer themselves or their 
progeny from bulb to bulb. 
M. Claparede says that the female of R. Robini has, when adult, 
a peculiarly thick and clumsy third pair of legs. The habits of the two 
are similar, but this species has been detected also upon the roots of the 
Potato and Dahlia ; R. echinopus may frequent these too, though as 
yet the fact has not been recorded. R. echinopus (also called Hypopus 
Dujardinii) was, it is thought, first observed by Boisduval, who called it 
Acarus Hyacinth!, on the supposition that it had a special liking for 
Hyacinths. The continental authors remark that persons who had to 
handle infested bulbs complained of irritation of the skin caused by the 
mites migrating to the human body ; this does not appear to have been 
noticed by our gardeners. It is probable that the autumn is the season 
when they propagate.—J. R. S. Clifford. 
ROYAL METEOROLOGICAL SOCIETY. 
The usual monthly meeting of this Society was held on Wednesday 
evening, the 21st ult., at the Institution of Civil Engineers, 25, 
Great George Street, Westminster, Dr. W. Marcet, F.R.S., President, 
in the chair. 
Dr. G. E. Scholefield and Col. W. S. Young were elected Fellows of 
the Society. 
The President, Dr. Marcet, delivered an address on “ Atmospheric 
Electricity.” He first alluded to Franklin’s experiments in America in 
1752, who succeeded in obtaining the electricity of a storm-cloud by 
conducting it along the string of a kite sent into the cloud. De Romas 
in Europe repeated the experiment, and having placed a wire within 
the twine his kite was attached to, obtained sparks of 9 or 10 feet in 
length. The characters of the two kinds of electricities were next 
described—the vitreous or positive, which was produced by rubbing 
glass ; and the resinous or negative, obtained by rubbing sealing wax 
or another resinous substance ; and it was shown by bringing sus¬ 
pended balls of pith within the influence of these electricities, that 
electricities of different kinds attract each other, and those of the same 
kind repel each other. De Saussure’s and Volta’s electroscopes were 
next described, pith balls being used in the former, and blades of straw 
in the latter, for testing the pressure of electricity. With the object 
of measuring the force of electricity. Sir W. Thomson’s electrometer was 
mentioned, in which the electricity is collected from the air by means 
of an insulated cistern, letting out water drop by drop, each drop be¬ 
coming covered with electricity from the atmosphere, which runs into 
the cistern, where it is stored up, and made to act upon that portion of 
the instrument which records its degree or amount. The atmosphere 
is always more or less electrical, or, in other words, possessed of 
electrical tension, and this is nearly always positive, while the earth 
exhibits electrical characters of a negative kind. 
The effects of atmospheric electricity were classed by Dr. Marcet 
under three heads—1, Lightning in thunderstorms; 2, The formation 
of hail ; 3, The formation of the aurora borealis and australis. He 
explained how clouds acquired their electrical activity by remarking 
that clouds forming in a blue sky, by a local condensation of moisture, 
became charged with positive electricity from the atmosphere ; while 
heavy dark clouds rising from below nearer to the earth were filled with 
terrestrial negative electricity, and the two systems of clouds attracting 
each other would discharge their electricity, giving rise to flashes of 
lightning. In some cases a storm-cloud charged with positive electricity 
would approach the earth, attracting the terrestrial negative electricity, 
and when within a certain distance shoot out a lightning which would 
apparently strike the earth ; but it would just as well have struck the 
cloud, only there was nothing in the cloud to sustain any damage, while 
on the earth there were many objects a lightning would destroy, to say 
nothing of its effects upon animal life. Thunder is the noise produced 
by the air rushing in to fill up the vacuum made by the heat of the 
lightning flash. There may be sheet lightnings, zii-zag or forked light¬ 
nings, and globular lightnings. The latter are particularly interesting; 
from their assuming a spherical form. Illustrations were given of objects 
struck by lightning, the most remarkable being, perhaps, the clothes of 
a working man, which were torn into shreds, while the man himself was- 
not seriously injured. 
Dr. Marcet next proceeded to show a flash of lightning, which he 
produced by throwing on a white screen the image of an electric spark 
2 or 3 inches in length, enlarged by means of the lens of an optical 
lantern ; forked lightning, 6 or 8 feet in length, with its irregular zig-zag 
course, was most clearly demonstrated. After alluding to the protecting 
