THE INSECT FAUNA OF THE ORANGE. 7 



pillars, with which to feed their helpless young. The Ladybirds (Coc- 

 cinellidaB) and their soft- bodied young, with other beetles seen upon the 

 trunk and branches, are busily engaged in the good work of tearing off 

 the scales of Bark-lice and feeding upon the Coccids and their eggs. 

 Wherever is found a tender shoot infested with a colony of Aphides, 

 there, in the midst of the swarming Plant-lice, will be found the slug- 

 like larvje of predaceous flies {Syrphtis, etc.), gradually but surely re- 

 ducing their numbers, in spite of the marvelous powers of reproduction 

 and fecundity of the Plant-lice. Upon the leaves the active young of 

 the Lace- wing [Ghnjsopa) may be seen trundling their little heaps of re- 

 fuse, beneath which the insect lurks in ambush for its prey. Among 

 the smallei' forms, whose operations are invisible to the unassisted eye, 

 are numerous predatory mites, which swarm among the Bark-lice, and 

 greatly aid in holding them in check. 



First in importance among beneficial insects, although least in size, 

 and most difficult of observation, are the true parasites, which live 

 within the bodies, and even inhabit the eggs of other insects, and, after 

 * having eaten and destroyed their host, issue as minute and active winged 

 insects. Few, if any, of the insect depredators upon the Orange are with- 

 out internal parasites, belonging with few exceptions to the By menopter a, 

 an order of four- winged insects of which the bees and wasps are types. 



Owing to their small size, and the concealment in which they pass 

 the greater portion of their lives, parasites are themselves seldom seen, 

 but the extent of their operations is sometimes rendered apparent by 

 the great mortality which follows their attacks upon an invading army 

 of plant enemies. Sometimes the presence of a parasite within its body 

 is indicated by a change of form or color which the parasitized insect 

 undergoes before its death, and in any case, after death, the work of 

 the ijarasite is plainly shown by the round hole which, in issuing, it 

 leaves behind in the body or the protective covering of its host. 



Innocuous insects. — Of these little need be said except that their 

 number is legion. Their importance to the agriculturist consists in the 

 liability of their being mistaken for noxious insects, and thus diverting 

 attention from the real depredators. 



Many harmless insects, which are so frequently seen upon the orange 

 tree that they may be considered its regular attendants, are to a certain 

 extent beneficial, and either feed upon the Various mosses and fungi 

 which accumulate upon the trunk and branches, or upon the lifeless 

 wood and bark of dead portions of the tree. 



Importance of distinguishing friends from foes. — Although 

 little can be done to increase the efficiency of beneficial insects, much 

 good can at times be accomplished by refraining from interference with 

 their operations. The orange-grower often does injury to his own in- 

 terests through lack of knowledge in distinguishing friends from foes, 

 and by the indiscriminate killing of all insects which he finds upon his 

 trees. 



