16 
Beck^ on a Coccus upon a Rosebush. 
already recorded^ and we as confidently predict its efficiency 
for a larger proportion of those observations which have 
yet to be made in that immense field of nature still un- 
explored. 
On a Coccus upo7i a Rosebush. 
By Richard Beck. 
(Read Nov. ISth, 1861.) 
In a note appended to my former paper on a coccus found 
upon oranges, and published in the ^ Microscopical J ournal ^ 
for July, 1861, I mentioned that the same insect was very 
numerous in our own gardens, and at that time my attention 
was directed to a plant of Cotoneaster against a south wall, 
which in many parts was literally covered with a female coc- 
cus of the same species as that already alluded to (PI. IV, fig. 1). 
The search for any males seemed, however, quite hopeless, 
when Mr. Cooke, the optician, of York, having written to me 
for some of the large garden spiders which he says are not to 
be found in his neighbourhood, I was hunting on a north 
wall, and could not but notice a Coccus in great abundance on 
the older stems of a rosebush, both the male and female 
insects being visible to the naked eye (fig. 2). For 
many reasons I for some time believed this to be a species 
entirely difterent from that on the orange ; the external ap- 
pearance of all the shields Avas very difierent, and when these 
were turned over the females were so much larger at the 
head as to be quite difi'erent in shape, and of a much darker 
colour (fig. 3). The eggs, also of a darker colour, were 
laid in a more or less circular position, and most of the males 
contained a fly entirely diff'erent from that I had previously 
described. 
But these were the only diflPerences, and ultimately, 
after a very careful examination, I traced both males and 
females, the former more especially, through exactly the 
same metaphorsoses as I have described in my former paper. 
The small fly I have alluded to as being present in some 
of the male shields, and, as I found afterwards, in those of the 
female also is a species of ichneumon (fig. 4), but its 
presence alters the external character of the Coccus very 
little, a slight enlargement in the males only being visible 
(fig. 5). 
Beneath the shields there are, however, considerable differ- 
ences ; in the female Coccus the mere fact of a fly being de- 
veloped is sufiicient to indicate an unnatiu^al state, and 
