WHEAT THRIPS ATTACK THE ONION. 



335 



bed bug and squash bug in structure, but differing from them 

 in having free jaws adapted to biting, while those of the bed 

 or squash bug form with the other mouth-organs a sharp, hard 

 beak, with which they puncture leaves or the flesh of their vic- 

 tims, when carnivorous in their tastes. These Thrips are fur- 

 ther distinguished by their wings being very long and narrow, 

 and beautifully fringed ; and when folded over their back they 

 do not conceal the body beneath, as is usually the case. More- 

 over, they are exceedingly active in their habits, running or leap- 

 ing like fleas. 



The females alone are winged, the males being wingless and 

 closely resembling the larvse. The body of the female 

 is smooth and shining, uniformly greenish yellow, with 

 no other markings ; the legs are a little paler towards 

 the articulations. The antennae are 8-jointed, slightly, 

 longer than the head ; the two basal joints are the 

 largest ; the three succeeding joints equal, regularly 

 ovate, the 6th a little longer than the 5th ; 7th and 8th 

 minute, 7th a little shorter than 8th, each joint bearing 

 four large bristles. This species differs from the Euro-<riH«(fem). 

 pean L. cerealium in having but eight joints, the 7th and 8th 

 being minute, and with no intermediate short one, as described 

 in the European insect. 



The prothorax is square, the scutel- 

 lum short, crescent-shaped, and the ab- 

 domen is long and narrow, smooth and 

 shining, 10-jointed. Length, four one- 

 hundredths of an inch, or less than half r 

 a line. 



The larva (Fig. 2), is entirely green-' 

 ish-yellow, the head and prothorax of- 

 the same color as the rest of the body. 3~ 

 The eyes are reddish. The feet and 7 r~ 

 antennae are whitish, not annulated, as 

 in L. cerealium. The feet (tarsi) con- 

 sist of but a single joint ending in a 



" " Larva and male of Limothrips tritici. 



The male differs from __^ ! f^f P f^~ v>xo a^fu^ 

 the larva in having 2- "^liiliiiij^^ 

 jointed feet (tarsi) and End of anlenncz of male _ 



Fig. 2. 



