CARROT APHIS OR GREEN FLY. 
13 
These little flies are only about the twelfth of an inch long, and hardly 
a quarter of an inch in the spread of their wings. The colour mainly 
black, legs bright ochre varied with black and brown, and the four 
wings transparent and iridescent.* 
The attack reported by Mr. Lowe from Sleaford appears to have 
been partial, for on October 14tli it was noticed that in many plots and 
gardens where Cauliflower and Broccoli leaves had been eaten to 
skeletons by Cabbage caterpillars no signs of the parasites were to be 
found; and at the same date the infested caterpillars, regarding which 
I was in correspondence, were reported to be continuing their migra¬ 
tion, seeking for suitable winter quarters in which to change to 
chrysalids. Many had gone up buildings, leaving parasite cocoons at 
intervals on the walls, and some also up a brick wall ten feet high, 
leaving parasites on the inner side. Of these Mr. Lowe sent me fine 
clusters, with destroyed caterpillars lying in the masses of cocoons. 
When the Cabbage caterpillar is going to tnrn to chrysalis it 
leaves the food-plant and creeps to any dry and sheltered spot, as 
under rafters, or boards in sheds, or under eaves or coping-stones, &c., 
out of doors, and the quantity of cocoons of the parasitic maggots 
found on the walls would be those that had come out of the Cabbage 
caterpillars on their journey to find a spot which their tenants 
prevented them needing. 
When cocoons are found in these large numbers they should not 
be destroyed, and, if necessary to sweep them down, it would be well 
to throw them aside safely in an open shed, where the flies might 
develop in spring and be of service in checking caterpillar-attack. 
CARROT. 
Carrot Aphis, or Green Fly. ? Aphis papaveris, Fab. ; ? Aphis 
carotte, Koch. 
On June 16th Mr. W. W. Glenny reported, from Barking, Essex :— 
“ The Green Fly is doing grievous damage among the Carrots ; the 
leaves are curled and look unthrifty. It is doubtful whether, even 
* The accompanying figure of Hemiteles melanarius 
(magnified, with lines showing natural size) repre¬ 
sents another kind of Ichneumon Fly, which preys 
similarly on the chrysalids of the Green-veined 
Cabbage Butterfly. It differs in some respects from 
the Microgaster, which has the “ ovipositor con¬ 
cealed beneath the abdomen,” but gives a general 
idea of the appearance of an Ichneumon Fly. 
