134 INSECTS AFFECTING THE ORANGE. 



in the northern part of the State. Both this and the preceding species 

 may be removed, as suggested by Mr. Ashiuead, by shaking them from 

 the trees into cloths spread to receive them. They fold up their legs 

 and simulate death, when disturbed. The early stages of both species 

 remain unknown. 



INSECTS OF THE ORDER ORTHOPTERA. 

 THE ANGULAK-WINGED KATYDID. 



{Microcentrum retinerve Burm.) 

 (Plate IX.) 



This large, green grasshopper, common in all parts of the United 

 States, has been exhaustively studied by Professor Riley, and its full 

 history detailed in his sixth Missouri report. It has been several times 

 noticed in reports of the Department, and is quite fully treated in the 

 report for 1880. The eggs — large oval objects, flattened like flax-seed 

 and dark gray in color, are placed overlapping each other in a row along 

 the edge of an orange leaf, or are deposited in two parallel rows along a 

 twig. There are two broods each year. Eggs laid in December hatch 

 in January or February. The young complete their growth in eight or 

 nine weeks. The eggs of the second brood begin to appear in May, and 

 are continually being deposited during the summer. Young of the sec- 

 ond brood are first seen in July. 



Throughout their lives, the Katydids feed upon the Or;mge. The 

 young confine themselves to the tender foliage, but the adults often 

 gnaw the bark of growing shoots and leaders, and thus inflict very 

 serious injuries. Occasionally a tree is almost defoliated by Katydids, 

 and this, of course, happens most frequently in the case of young trees ; 

 but, owing to the luxuriance of its foliage and the rapidity with which 

 the orange-tree renews its lost leaves, the damage done by these insects 

 is rarely sufficient to repay the cost of fighting them. Young groves 

 should, however, be protected from their attacks, and early in the winter 

 the trees should be examined and the leaves with eggs upon them re- 

 moved. The young may very readily be killed by dusting the foliage 

 with pyrethrum powder. 



Egg-parasite of the katydid. — (Eupelmm [Antigaster] mirahilis, 

 Walsh.)— (Plate IX, Fig. 2, female; Fig. 2a, male.)— The eggs of the 

 Katydid are very frequently found with a small, round hole cut through 

 the side. This is the exit-hole of the i)arasite which is hatched and 

 bred within the egg of the Katydid, feeds upon its contents, and in due 

 course issues forth, a four-winged(flyJ The larva, like that of most 

 Hymenopterous parasites, is a transparent, white, footless grub; the 

 pupa of the female is flattened, and is very curiously packed in its nar- 

 row quarters, so that it exactly fills the space within the egg-shell. To 



