2 
Que RETT, on the Mealy Bug of the Vine. 
of not less than 250 diameters, it is found to consist of a 
series of sliort filaments or cylinders, some of wliich are 
straight, but others more or less curved ; within each cylinder 
is a tubular cavity, extending throughout its whole length. 
That this is a tube may be well shown by the addition of 
water, which will readily enter both extremities of the tube, 
and render these parts more transparent than those containing 
air. The diameter of the cylinders is on an average ^oVo^h 
of an inch, whilst that of the tube within varies from -y^^o ^th 
to QoVoth- The majority of the cylinders, when divided 
transversely, are found to be of circular figure, but I have 
occasionally seen them slightly flattened on one side. 
" In fig. 1 (PI. I) , you have a representation of the cylinders 
as seen under a power of 500 diameters. If the wax be heated 
on glass it readily melts when the temperature rises to 184° 
Fahrenheit ; and if examined in this state, the fluid mass is 
perfectly transparent and structureless. On cooling, however, 
it crystallizes precisely like spermaceti, as shown in fig. 2. I 
have also made a microscopical examination of the insects, 
but have not been able to discover as much of their internal 
organization as I could wish, in consequence of their dried 
and shrivelled condition. One of the most perfect specimens 
that I could select from upwards of a dozen which I took out 
of one of the rounded masses of wax before alluded to, is 
represented in fig. 4 ; this is its dorsal surface. Fig. 5 is a 
representation of the abdominal surface of the same insect. 
It will be seen that it has six legs, and the body is full of 
wax. In one of these insects, which appeared more transpa- 
rent than the rest, the circular aperture or mouth was more 
plainly seen than in the specimen represented by fig. 5 ; but 
from the injury all the insects had sustained, I could not 
ascertain more of their intimate structure. Mr. Hanbury 
having, through the kindness of Sir W. Hooker, obtained 
some of the living cochineal from Kew Gardens, brought me 
a specimen of the white matter with which the insects are 
surrounded for comparison with that of the insect wax, and I 
find that it is composed of two distinct substances, one oc- 
curring in the form of filaments, and the other in minute 
oval bodies, which I shall term cocoons; these are about 
i^oth of an inch in the long, by -i^i^ in the short diameter. 
When these last were examined microscopically, they pre- 
sented nearly the same structure as the insect wax, but the 
filaments were of two kinds ; one which made up almost the en- 
tire bulk of the cocoon was of small size, averaging q-^qqUl 
to T^oTTiytl^ of an inch in diameter ; whilst the others, which are 
met with in fewer numbers, and on the outside of the cocoon, 
