140 INSECTS AFFECTING THE ORANGE. 



across the middle. The wings are smoky. The head and thorax are 

 very coarsely punctured, and clothed with short, golden hairs. The 

 fly in quitting its host makes a large, round hole in he side of the 

 chrysalis. All the specimens obtained emerged in June or July from 

 pup* of the second brood. There can be no doubt that this parasite 

 would in case of undue multiplication of the Orange Dog become an 

 efficient check upon its increase. At present, however, it is somewhat 

 rare. 



SLUG CATEEPILLARS STINGING CATERPILLARS. 



Several species of Bombycida3, called "slug caterpillars," because of 

 their apparent want of legs, and their gliding, snail-like movements, are 

 occasionally found doing damage to orange trees by feeding upon the 

 leaves. The hairy species-are known as " stinging caterpillars," being 

 provided with nettling hairs. They are all of rather large size, an inch 

 or more in length, and have sluggish habits. They construct stout and 

 very tough cocoons, attached to the bark of the tree, and they know 

 how to conceal them with great art. The perfect insects are moths, 

 with rather thick, heavy bodies, covered with long, downy hairs, and 

 flying only at night. The four species which are known to feed upon 

 the Orange are Lagoa opercularis Sm. & Abb., Empretia stimulea Clem., 

 Phobetron pithecinm Sm. & Abb., and Limacodes scapha Harr. 



LAGOA OPERCULARIS Sm. & Abb. 



[Figs. 57, 58, 59.J 



The caterpillars of this moth are covered with long, silky hair, under- 

 neath which are concealed shorter, stiff hairs, exceedingly sharp at the 

 points, and powerfully nettling when they pen- 

 etrate the flesh. Upon some persons the invis- 

 ible wounds made by these hairs produce swell- 

 ings, and an amount of irritation equivalent to 

 a sting; the larvre are, in consequence, popular- 

 ly supposed to be very poisonous. When young 

 the caterpillars are white and resemble a flock 

 of cotton wool. They undergo six molts, at one of the last of which 

 they become darker, the color varying in individuals, from red-brown to 

 light clay-color. When full-grown the larva presents the singular ap- 

 pearance of a lock of hair possessing sluggish life and a gliding, snail- 

 like motion. It is 1 inches long, bluntly rounded in front and dimin- 

 ishing rapidly to a point behind. The hair rises in a sharp ridge upon 

 the back, and forms several tufts of rust-red color. 



The cocoon (Fig. 58) is placed in a crotch of the tree or upon a branch 

 of considerable size; it is 20 mm (-ft- inch) long, oval, convex, flattened 

 on the side next the tree, and fastened very firmly to the bark. The 

 upper end is abruptly truncate, and fitted with a hinged trap-door, 



