Mr. F. M^alker on the Migrations 0 / Aphides. 373 
sloe, and the hop-grounds now provide it with a plentiful 
provision in the summer. Its presence on the hop is depen- 
dent on the proximity of the sloe to the hop-grounds, and these 
plantations should be inspected, and the extent of the sloes 
in the vicinity and their distance from the hops ascertained, and 
the length of the flight of the Aphis should also be observed, 
in order that the hop and the sloe may in time be kept suffi- 
ciently remote from each other to conflne the Aphis to the latter 
plant and thus to prevent its injuring the hop. A. Ulmariae 
dwells on the broom, and the meadow-sweet is its summer food, 
and the cultivation of sweet peas, peas, beans, clover, tares, 
vetches, saintfoin, &c. has added greatly to its means of subsist- 
ence. A, Lactucce is very abundant on the sow-thistle and some 
allied plants, and its oeconomy is modifled by the presence of the 
lettuce and the black currant in gardens, to both which plants 
it is very partial. A. Brassicce feeds especially on the sea-kale 
in a wild state, and also on the wild mustard, and the introduc- 
tion of the cabbage from the South of Europe has added to its 
food in this country. A, Pruni has settled on the plum since 
that tree was brought into Europe, and it has received the name 
of A. Arundinis from its feeding on the reed, which is its earliest 
habitation. A. Mali and A. Sorbi dwell on the white-thorn as 
well as on the apple, the service, the medlar and the mountain- 
ash. A. Persicce is so named from its having fixed itself on the 
peach since that tree was planted in Europe, but its other name, 
A. Prunicola, denotes its primitive habitation and food. A. 
Juglandis and A. Juglandicola have accompanied or followed the 
walnut in its successive cultivation westward from Persia, which 
is its native country, and that of the peach and of the apricot. 
A. Ahietina has probably come into England with the spruce fir, 
and a few other species that feed on the fir-tribe may have also 
been brought over from the continent. A. Bubi abounds on the 
bramble and on the raspberry, and during the summer is also 
common on Geum urbanum, the common Avens, and on a species 
of Epilobium or willow-herb. A. Dianthi (otherwise named A. 
vulgaris and A.Rapce and A.vastator) feeds on a very great variety 
of green-house plants. The furze seems to be the principal 
winter-quarters of A. Rumicis, and I observed that it swarmed 
])rofusely and laid its eggs on that plant in the autumn of 1846, 
and the following year was remarkable on account of the devasta- 
tions of this Aphis in the bean-fields ; it feeds also on the labur- 
num, the poppy and the dock, and on very many other plants. It 
was unusually abundant on the laburnum last year, and great 
numbers of humble-bees came to feed on its honey. The lady- 
bird [Coccinella 7 -punctata) was also extremely common with 
this Aphis, and it promises to be equally so this year, for great 
numbers have already appeared during ^larch and April. 
