804 [Assembly 
approach of a fly or other insect, the pupa gives a sudden spiteful 
jerk, by which to frighten the intruder away,aud if this fail 1 ', by 
a sudden spring it elevates itself so as to stand out at right angles 
from the surface to which it is attached, remaining motionless in 
this posture about a half minute, when by a similar spasmodic 
snap it returns to its usual position. 
The insect remains dormant in its pupa state about a fortnight, 
when its hard exterior shell cracks open, and from it crawls a 
small shining beetle nearly the size and shape of a half pea, 
though often much smaller than this. The species generally are 
prettily colored, being bright red, yellow or white, with black 
spots, or black with red or yellow spots. These different spots 
and colors serve as marks whereby to distinguish the different 
species, of which nearly a hundred are named and described, in¬ 
habiting the United States. The perfect insects subsist upon 
plant lice also, though they pursue and devour them with less 
avidity than when in the larva stage of their lives. They may 
always be met with where plant-lice abound, and I have known 
persons who supposed that it was these insects w r hich bred 
the plant-lice, and who consequently made it a point to destroy 
every one which they could discover upon the currant bushes, 
cherry trees, &c., in their yards, and who were surprised to find 
that notwithstanding all their care and pains in searching out 
and destroying these “ old ones,” their shrubs and trees appeared 
every year to be worse infested with lice than were those of their 
neighbors. This fact is but one of a multitude which might be 
adduced, showing to what sad mistakes ignorance leads, and how 
important it is that information with respect to our insects and 
their habits should be diffused among our citizens. 
Other inveterate enemies of the plant-lice are certain two- 
winged flies pertaining to the Family SyupHiniE, in the Order Dir- 
tera, which family has the genus Syrphus as its type. These 
flies resemble our common house fly in size and shape but are 
much handsomer, being of a bright yellow color with various 
spots and bands of black, according to the species. They may 
frequently be seen in summer hovering around and alighting 
