JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
112 
[ August 4, 1881. 
spondents says it has haulm 5 feet high, and another that it has 
nine or ten peas in a pod.—G. S., Sandbeck Park. 
CHAPTERS ON INSECTS FOR GARDENERS.—No. 26. 
NEW SERIES. 
In previous articles that have been comprehended in this series 
some account has been given of the galls produced upon trees and 
plants by various two-winged and four-winged flies. Many of the 
larger galls serve as homes or resorts for more than one species of 
insect, and the concluding page in the history of most that are 
left undisturbed is their demolition by small parties of Acari or 
mites, though some escape for a long time, as for example the 
well-known oak-gall (fig. 20). This, the marble or Devonshire gall, 
is the work of Cynips Kollari, a four-winged fly, and rightful occu¬ 
pier while a grub of the central hole, into which, however, parasites 
occasionally intrude and devour it before it is mature. In addi¬ 
tion to these we also find in the galls what are called the “inqui- 
lines,” or fellow-lodgers. Their abodes are scattered throughout 
the substance of the gall. To obtain the insects within these 
galls titmice and other birds drive holes in them, and the effect 
of the weather so softens them ultimately that mites can break 
them up and feast on their contents. 
But we have also a group of mites that are actually the pro¬ 
ducers of galls, and to a moderate extent several species are found 
to be not merely disfigurers—they check growth or develope an 
unhealthy action in the plants they attack. So doubtEul was their 
history during the early years of scientific research, that not a few 
of our naturalists were led to regard the galls caused by mites as 
simply instances of fungoid or other vegetable growths induced 
by the state of the air. With ordinary galls there is seldom any 
difficulty, when a number are examined, in detecting the tenants 
or some traces of them ; but the tiny, and occasionally almost 
transparent, mites escaped observation until the experiment was 
Fig. 20.—Oak Galls. 
made of soaking the galls in water and examining the solution. 
Most persons have noticed at some time or other upon the leaves 
of the Lime numerous little projections that from their shape 
have received the name of “nail-galls,” and in which, when they 
are cut open, we perceive nothing but a crowd of minute vegetable 
hairs. Reaumur, one of the highly honoured entomologists of 
France, saw these a century and a half ago, and he presumed that 
insects had to do with them ; after a good while he found some. 
From his description, however, these must have been creatures 
preying upon the mites. It was not until the year 1851 that the 
producers of these nail-galls were detected by M. Dujardin, and 
the species was named Phytoptus Tilise ; it is one of those that 
are semi-transparent. 
It is not necessary to describe fully the habits of the Phytop- 
tidas or gall-mites, but it may be stated that they live usually in 
colonies composed of both larvae and mature mites, the larvae in 
some species having only four legs. The head of the mature in¬ 
sect is hardly distinguishable from its body. It is furnished with 
short thick palpi, and the legs appear to be not only clawed at 
the tips, they have also beside the hard claw a moveable soft one, 
or sucker. Yet it is curious that these mites are not particularly 
fond of locomotion. “ They waggle about in an aimless way, 
turned from their path by any obstacle, such as meeting one of 
themselves,” writes Mr. Murray, who has been so fortunate as to 
see some crawling about; and yet, for all that, they manage to 
spread themselves over a whole tree or an entire hedge. For 
although they will infest the same plant year after year if not 
meddled with, they also appear in new localities. And here is 
a puzzle : What becomes of the gall-mites that infest buds when 
there are no buds for them to consume— i.e., during the greater 
part of the year? They vanish from the plants, and no one 
can say where they go ; but they re-appear sure enough in their 
proper season. The Phytoptidae (as might be supposed) occurring 
within buds are principally injurious. They do not form dis¬ 
tinct galls like the leaf-infesting species ; they give to the whole 
bud a rounded puffy aspect, the leaflets within look “raw,” and 
eventually the bud decays and drops. Nor is the result by 
any means salutary to the plant. We have never been able to 
perceive these with the unassisted eye; with a good hand-mag¬ 
nifier they may be observed, even if they are quiescent. P. 
taxi, described in the Gardeners' Chronicle with doubt as a Te- 
tranychus or a spinning mite in 1875, was perceived by Pro¬ 
fessor Thistleton Dyer to be doing damage amongst the Yew 
hedges about London, the buds appearing as if they were frost¬ 
bitten. In Europe species have been found upon the Hazel 
and the Peach which at present have not occurred in England. 
The most familiar example of a bud-mite is P. ribis, which has 
occurred upon the Currant throughout Britain, being, however, 
more common in Scotland than in England. Hundreds of mites 
are congregated in a single bud, and each one that is touched 
shrivels up, perhaps the branch also dies off. Mr. Murray, con¬ 
cluding that the mites are lodged about the buds late in autumn, 
advises close pruning as an effective check. 
The gall of the Lime has been already referred to ; still more 
conspicuous is the gall that occurs upon the Sycamore, which is 
always red or purple. The Lime nail-gall is mostly reddish at 
one period, fading into brown. P. aceris developes these Syca¬ 
more galls, and also, probably, the crowded hairy galls usual on 
the under side of Maple leaves. The Pear has its special mite foe 
in P. pyri, an insect which, it may be, prefers a warmish tempera¬ 
ture, since its prevalence on the Continent is greater than in Eng¬ 
land. It is chiefly on the young leaves that the Pear mite shows 
itself, covering them with unpleasant-looking blotches, at first 
pale red, afterwards black. In the swellings are minute holes, 
either made by the older mites for the purpose of exit, or else 
made by a parasite enemy of the mites. Upon the Plum, pro¬ 
duced by P. pruni, galls are commonly noticeable ; these appear 
on both sides of the leaf, rounded like purses or little bags, oc¬ 
casionally club-shaped. White hairs frequently grow outside 
these galls, the interior being full of hairs, as is usual. Foreign 
observers have discovered more than one species upon the Apple ; 
these, though unnoticed here, may occur with us. In these 
instances of fruit trees thus affected no actual injury is done by 
the mites. A special interest belongs to a gall-mite taken upon 
the Vine, named Phyllerium vitis, because its effects seem by 
some gardeners to have been ascribed to the work of the Phyl¬ 
loxera. This mite developes warty spots or patches on the under 
side of the leaves, and it is very difficult to discover. Botanists, 
indebd, for a long while supposed insects had nothing to do with 
these patches. What have been called “ the clusters ” of the 
Ash have now been proved to be morbid growths by myriads of a 
gall-mite, glossy in appearance, and excessively small. The parts 
attacked are the styles of the flower, w'hich increase to a mon¬ 
strous size, turning a greenish or blackish brown. The “ clusters ” 
are dotted with hairs on the upner side, and they become very 
hard ; there is no hollow within them. Passing over many others, 
we can only add that a species of Phytoptus visits the Strawberry, 
making its home in galls which arise from its punctures. These 
are short, very hairy, and purplish, set thickly together in the 
leaves.—J. R. S. C. 
THE ART OF COLOURING GRAPES. 
It is pitiable to see Grapes which are fine in every other way— 
large and regular in berry, beautiful in form, and large in size of 
bunch—yet lacking that all-important point of excellence, good 
colour, and consequent good flavour. It is possible to have good 
colour without good flavour, inasmuch as colour under good culti¬ 
vation will come first, but it is not possible to have good flavour 
without good colour. I do not say that Grapes should be all either 
black or yellow ; there are some of the best flavoured varieties 
which will not, under any system of cultivation, approach either 
of these colours, and are therefore not so much grown as their 
merits would warrant; but when we see, as all of us who attend 
exhibitions do see every year, red Grapes conspicuously labelled 
Black Hamburgh, and Muscat of Alexandria as green as a Leek, 
we may be sure there is something wrong either in the culture or 
nomenclature. At local shows especially, judges have an un¬ 
thankful office to perform when size is pitted against finish, and 
of course everybody is on the side of the giants. At the larger 
shows, in consequence of a greater number of persons attending 
who know what a bunch of Grapes should be, and there being 
amongst the crowd a certain amount of confidence in the great 
men who are supposed to act as censors on such occasions, the 
task of judging is not so thankless. 
