186 



INSECTS AFFECTING THE OKANGE. 



tious of the Ai)]iis-eatiiis' Syrplius-iiies will apply equally to this iu,'.-ect, 

 aud it is found in comi)auy with them not alone upon the Orange, but 

 among various species of Aphis on other plants as well. 



Parasite. — A minute Hymeuoiiterous fly (a Pteromalid)'® attacks the 

 larva and issues from the i)ui)arium through round holes eaten in its 

 side. Two specimens of the parasites were bred from a single puparium 

 of the fly. They issue in September. 



OTHER PREDATORY INSECTS FREftUENTING THE ORANGE. 



Fig. 87. — Polistes avxericamis 

 Coiu.stock.; 



(After 



peedatoey wasps. 



POLISTES AMERiCANUS (Fabr.). 



[Figs. 87 and 88.J 



This large red wasp is fond of making its home under the den.'^e foliage 

 of the orange tree, and suspends its comb of paper to the branches. 



It is a large s[)ecies, and it;; sting is 

 equal in severity to that of the-white-faced 

 hornet. Fortunately, it is not an iiritable 

 wasp, and is little inclined to use its 

 weapon, except- when its nest is attacked. 

 Like most insects of its kind this wasp 

 is carnivorous, and to a great extent preys 

 npou caterpillars and soft-bodied insects. 

 With these it feeds its young, first masti- 

 cating the food into a pulpy ball, in order 

 that it may readily be swallowed b^" its 

 young, W'hich are not providtd with horny jaws, and then presenting it 

 to the latter in their cells in much the same fashion that a bird feeds 

 its nestlings. Not only the grubs are fed in this way, but also the young- 

 wasps which have recently issued from the pupa, and 

 which do not for some time leave the nest or take part 

 in the labors of the colony. 



The nest consists of a single comb or layer of cells, 

 which is increased in size by the addition of new cells 

 around the edges until it sometimes attains the diam- 

 eter of 10 or 12 inches. The comb is not protected by 

 a covering of paper, as in the nest of a hornet, but 

 the cells are built with the mouth downwards, and 

 the back of the comb is made very thick and strong, 

 so that it sheds water. 

 The wasps make their comb of wood masticated to a pulp. They may 

 be seen gathering for this purpose from fence rails and unpainted wood 

 surfaces the fibers beaten out by the action of the weather. The leaf- 

 rolling cateri)illars which injure the buds and tender shoots of the Or- 

 ange form a very considerable portion of the food of all colonies of Pol- 



FlG. B8.— Polistes nest 

 in spring. (After 

 Riley.) 



