418 INSECTS INJURIOUS TO THE ORANGE. 



In addition to the species already named, the following are 

 worthy of mention : 



Exochcmus contrktatus Muls. This is a small lady-bird, 

 about one-seventh of an inch long, of a red color, with a black 

 thorax and two black spots on the wing-covers, placed near 

 the hinder end. The larva is about one-sixth of an inch 

 long, yellowish, with black spots and spines. Both the larva 

 and beetle are useful in destroying scale-insects, and are quite 

 common among the orange groves. 



Scymnus cervicalis Muls. A hemispherical beetle, about 

 one-tenth of an inch long, of a reddish-brown color, with 

 dark-blue wing-covers. Its larva is pale whitish, with a few 

 scattered hairs, the head small, round, and black. 



Scymnus bioeulatus Muls. The larvae of this beetle have 

 been found feeding on the eggs of the mealy-bug ; they are 

 covered with a white secretion, something like the mealy-bug 

 itself, and hence are not easily discovered. 



Hyperaspidius coccidivora Ashmead. This beetle, which 

 resembles a minute Scymnus, also destroys many of the 

 scale-insects, and is especially destructive to the chaff scale. 

 It is about one twenty- fifth of an inch long, oval, of a 

 dark color, having a polished surface and a reddish patch 

 on each wing-cover. 

 Fia. 437. The orange Chrysopa, Chrysopa 



citri Ashmead. This is a lace-wing 

 fly, of a bright yellowish-green color, 

 with antennae longer than the trans- 

 parent, netted wings, and having 

 bright, golden eyes. (See Fig. 437.) 

 Its eggs are laid on long, thread-like 

 stalks, and the larva, which devours both scale-lice and plant- 

 lice greedily, covers itself with minute pieces of dried leaves 

 or other light substances. It is pinkish, mottled with brown 

 spots. 



Artificial Remedies. — From the suctorial habits of the 

 bark-lice, the remedies available are limited to such as 



