180 
BEITISH APHIDES. 
May, a most nnusual time of year for the occurrence of 
any male of the family Aphididse. 
There can be but little doubt, that Aphis insititia of 
Koch, feeding on the wild plum, is identical with this 
species. 
Myms persiccB is common on both the peach and 
the nectarine. The winged form may appear as early 
as the first w^eek of May. In June I saw Aphides 
taken from the apple tree, which in form and colour 
could not be separated from M. persicm. In October, 
1870, these insects appeared in immense numbers on 
the peach trees at Clifton, near Bristol, and they 
much alarmed the neighbouring non-naturalists as 
to the safety of the trees. Schneidberger says this 
Aphis has sixteen generations before the occurrence of 
the oviparous female. We cannot doubt, however, 
that climatal and such like causes must make the 
above periods of birth very uncertain. 
The beautiful colour of this Aphis is mainly caused 
by a quantity of highly refractive globules of pink oil, 
which mass themselves in various parts of the body, 
and particularly so at the roots of the cornicles. 
These last organs are often fully charged with them. 
Myzus eibis, Linn. Plate XXXIV, figs. 1 — 4, 
Aphis ribis, Linn., Pabr., Schr., Kalt., Walk. 
Bibifex, Amyot. 
Bhopalosiphum ribis, Koch. 
Myzus rihis, Pass. 
Apterous viviparous female. 
Inches. 
Size of body 0‘085 X 0*040 
Length of antennae 0*090 
,, cornicles 0*015 
Millimetres. 
2-14X101. 
2-27. 
0-37. 
Long oval. Shining yellow or green, with darker 
green mottlings. Front flat, garnished with short 
