CALENDAR FOR MARCH. 
71 
CALENDAR FOR MARCH. 
The enthusiast in flowers will find the number of his enemies 
increase as the season draws out, and his favourites begin to 
dev elope their beauties. The green-flv, the thrip, and the red 
spider will begin to multiply as the light and heat of the year 
becomes of greater duration. It will, therefore, be worth while 
to take a slight review of these enemies, and of their points of 
attack, in conjunction with the best means of getting rid of 
them. 
The species of green-fly are very numerous, especially if we 
consider as such the individuals of the different genera— 
Aphis , Cinara , and Eriosoma —which we may conveniently do in 
the present case, from their similarity of appearance and eco¬ 
nomy. Taking them therefore collectively, we include the com¬ 
mon green-fly, as well as the American blight which infests apple 
trees, the similar insect which is found in great quantities about 
the roots of lettuce plants, especially in summer and autumn, and 
many others, for there is scarcely a plant that is not infested with 
them, more or less, and on different plants the species of insects 
are also very often different, whilst some, as the oak, are attacked 
by many species of these insects. 
The species of thrip appear to be far less known than the 
green flies, but there is no doubt they are very numerous. They 
commit great ravages on the tender shoots and leaves of plants, 
by puncturing them and extracting the sap, leaving the parts of 
a dry brown, dried up consistence. The examination and deter¬ 
mination of the different species of these minute insects would 
be a source of great interest to an amateur gardener with sufficient 
leisure. 
Little doubt can be entertained that there are also several species 
of red spider; but, like the last named insects, they have not 
received that attention which the extent of their ravages demand. 
In some seasons they are so numerous as to materially injure the 
foliage of trees, especially those of the lime, whilst in hot-houses 
they are sure to be very destructive, if the house is kept in too 
dry a state. 
