184 
Publications oj Interest to Agriculturists. 
fruit trees with Paris Green for the winter moth and the weevil 
than to visit every day bands of tar encircling the trees to catch 
the one, or to shake the boughs continuously to dislodge the other. 
Very pertinent remarks are made as to the mode of putting on 
insecticides, which should be applied in the form of a mist, and not 
as deluging showers. The object should be to cover each leaf with 
a light layer ( mince couche) of the substance, and for doing this 
M. Dangeard states there is no machine better than the Eclair. 
Two pseudo-insects, or creatures allied to insects, are described 
here as belonging to the Acaridce ; one, a species of Tetranychus , 
and the other a Phytoptus. This Tetranychus , termed by Donnadieu 
Tenuipalpus glaber, causes the discoloration of the leaves of apple 
and pear trees by sucking out their juices and eventually making 
them shrivel and fall off. 1 They are always on the lower surfaces 
of the leaves, and about October the 7th, M. Dangeard remarks, they 
leave them, and retire for the winter to the twigs, where they 
shelter themselves in the fissures of skin or bark, under lichenous 
growths, and between the scales of the buds, still sucking up sap, 
and unaffected by sharp frosts. When the leaves appear the mites 
go to them. From the habit of this species of Tetranychus, 
M. Dangeard argues that the Tetranychus telarius, spinning mite, 
or “ red spider,” so injurious to hop plants, damson trees, peach 
trees, gooseberry bushes, strawberry plants, and many other trees and 
plants, likewise retires to the twigs, branches, and stalks of its host. 
This is an important deduction, and if confirmed will enable cul- 
tivators to deal with this universal pest during the winter. It is not 
known whether the Tenuipalpus glaber attacks apple trees in Great 
Britain. The Tetranychus telarius does, or at least a Tetranychus 
of some species, which has so far been taken to be Tetranychus telarius, 
but may be Tenuipalpus glaber, in default of close observation, 
though there are marked distinctions between the two species. 
Petroleum washes applied both in winter and summer are recom- 
mended as valuable remedies for this mite. 
M. Dangeard notes that a fungus, Pestalozzia concentrica, is fre- 
quently found in the spots ( taches ) caused by these mites, which serves 
to finish the ruin of the leaves already almost exhausted by their 
attacks. Also, in the case of apple and pear leaves infested by a 
species of Phytoptus described by Sorauer as Phytoptus piri , 2 M. 
Dangeard remarks that the evil effects of this mite are often much 
aggravated by the presence of a fungus of a Fumago type in or upon 
their galls. For this double attack, which is not uncommon in Eng- 
land, it is recommended that all fallen leaves should be carefully 
collected and burnt. The leaves should be treated in the summer 
with bouillie bordelaise , which would arrest the fungus and serve as 
an obstacle to hinder the Phytoptus from penetrating their epi- 
dermis. 
The most useful and interesting chapter is upon the canker 
This is termed la ma/rbrure des feuilles by M. Dangeard. 
Randbuch von Pjianzenkranliheiten, von Dr. Saul Sorauer. 
