Beetles 
287 
spots. Their colors and markings make them conspicuous, and vet the 
natural enemies of insects, the birds, obviously let them alone; it is presumed, 
therefore, that these beetles are ill-tasting to birds, and that their bright colors 
are of the nature of readily perceived warning signs (see discussion of. 
this subject in Chapter XVII). 
The eggs are laid on the bark, stems, or leaves of the tree or plant on 
which aphids or scale-insects are present. Sometimes they are deposited 
in little patches right in the middle of a colony of plant-lice. The larvae 
(Fig. 398) are elongate, widest across the pro thorax and tapering back to 
the tip, with the skin usually roughened or punctate, bearing hairs and short 
spines, and marked with blackish, reddish, and yellowish. The larvae feed 
steadily on the soft defenceless aphids or young scale-insects, or on the eggs 
and young of other larger insects. When full-grown they pupate, attached 
to the leaves or stems without entirely casting off the last larval exuvia (Fig. 
398). This cuticle often surrounds the pupa “like a tight-fitting overcoat 
with the front not closed by buttons.” In other cases the larval skin is 
forced backwards and remains as a little crumpled pad about the posterior 
end. 
The two-spotted ladybug, Adalia bipunctata , reddish yellow with a 
single black spot on each elytron, is common in the East, where it often 
enters houses to hibernate. The nine-spotted 
ladybird, Coccinella novemnotata, has yellowish 
elytra with four black spots on each in addition 
to a common spot just behind the thorax. 
The “twice-stabbed” ladybird, Chilocorus 
bivulnerus, is shining black with a large red 
spot on each elytron. Anatis 15-punctata, the 
fifteen-spotted ladybird, is a large species with 
dark brownish-red elytra bearing seven black 
spots each, and a median common spot just 
behind the thorax. 
In California the ladybirds are of great 
importance to the fruit-growers, their steady 
wholesale destruction of scale-insects being an 
important factor in successful fruit-raising. Fig. 397 illustrates eight species 
found on the Pacific coast. A number of ladybird species have been imported 
from Australia and other countries from which numerous destructive scale- 
insects had been earlier unwittingly brought on nursery stock. Most conspic¬ 
uously successful of these attempts to introduce and disseminate original home 
enemies of imported pests has been the establishment of the small red-and- 
black ladybird, Vedalia cardinalis, which feeds exclusively on the fluted or cot¬ 
tony cushion-scale ( Icerya purchasi) (Fig. 254). This Australian scale first 
m 
Fig. 398.—A ladybird-beetle, 
Coccinella californica; larva, 
pupae, and adult on Lawson’s 
cyprees. (Twice natural size.) 
