14 
BULLETIN 843, IT. S. DEPARTMENT OF AGRICULTURE. 
Fig. 3. — The five-spotted ladybird 
(Hip pod a mi a 5-signata) , an 
enemy of the bean ladybird. 
Enlarged. 
northern climates. This is not a theory but is based on facts. It is 
indicated by the fact that many eggs, larvae, and pupae occur so late 
in the fall that they are killed by freezing. Many larvae starve be- 
cause the foliage of the bean plants on which they had been feeding 
was destroyed by early fall frosts. It 
is also not uncommon to find many 
dead adults in their hibernating quar- 
ters where they had been killed by 
winter temperatures. 
NATURAL ENEMIES. 
The insect enemies of the bean lady- 
bird are, as far as has been learned, not 
particularly effective in holding it in 
abeyance. The beetles are well pro- 
tected by their firm elytra or wing cov- 
ers and by a repellent yellow liquid 
which oozes from their knee joints in 
small drops when the insects are disturbed. This liquid possesses a 
disagreeable odor and doubtless a similar flavor, which, it is believed, 
may protect the beetles from the attacks of natural enemies. 
June 27, 1916, two overwintered female beetles were collected at 
Kocky Ford, Colo., each with the egg of a tachinid fly attached to- 
one of its elytra. One of these beetles 
died September 4, and the other Sep- 
tember 9. Fertile eggs were depos- 
ited at frequent intervals from June 
29 until September 5, and no 
parasites developed. This is the only 
evidence noted of insect parasites. 
Morrill has reported an undeter- 
mined ant observed eating the eggs 
on one occasion. 
The adults of three species of pre- 
dacious ladybirds are known to be 
natural enemies of this insect. They 
The convergent ladybird 
are 
Fig. 4. — Transverse-spotted lady- 
bird (Coccinella transversogut- 
tata) : Adult beetle. Much en- 
larged. 
(Hippodamia convergens De G.) ; 
the five-spotted ladybird (Hippo- 
damia 5-signata Kby., fig. 3), and 
the transverse-spotted ladvbird (Coccinella transversoguttata Fab., 
%. i). 
These have been reported as destroying the eggs of the bean lady- 
bird, and next to cold are the most effective known factors in its 
natural control in Colorado and neighboring States. 
