« 

 Jan. IS. I9IS ■ Three-Cornered Alfalfa Hopper 347 



Body yellowish-green: thorax unarmed, carinate behind; at tip attenuated, subu- 

 late and complying with the general curvature; each side before a carinate line, 

 meeting together at the carina behind the middle, with the carina tinged with rufous: 

 front of the thorax not altogether fiat, but a little convex; hemelytra, three terminal 

 cellules unequal; the two costal ones equal, as broad as long; the inner one not 

 obviously larger than the others together, somewhat longer than broad. Length to 

 tip of hemelytra one fifth of inch. The lateral prominent lines of the unarmed thorax, 

 separate this species from all those I have described excepting goniphera, which, 

 meet before the middle of the length of the back. 



THE EGG 



The egg (PL XLIII, fig. 2, b) is about 1 mm. (0.9 to i .3 mm.) long and 

 0.35 mm. (0.25 to 0.4 mm.) in diameter. It is white, rather oblong, 

 slightly larger at one end, and with a greater curve on one side. The 

 surface is smooth, except a portion on the larger end which is regularly 

 covered with small papillae. 



THE NYMPH 



The nymphs are the same general shape as the adults, but instead of 

 having the prothoracic shield as a body covering, the}' are regularly 

 covered with prominent projections, spines, and hairs. There is one 

 dorsal pair of these projections on the head, four pairs on the thorax, 

 and seven pairs on the abdomen, the posterior pair on the anal segment 

 being much reduced in size. 



Their general color is as follows : Head and thorax very light straw. 

 Eyes with margin white and center cologne earth. Antennae white. 

 Thorax with a regular cologne-earth patch on each side, widest on the 

 raesothorax, where it reaches the darkest shade. Legs white, except tip 

 of last tarsal joint, which is dark brown. Abdomen white, approaching 

 light green, owing to food material within, with the irregular dark spot 

 of the thorax extending narrowly across the first segment, widening 

 greatly on segments 2, 3, and 4, and showing only on the posterior margin 

 of the fifth, being widest on the posterior margin of segments 3 and 4. 

 Anal segment light-straw color at extreme end. 



The different nymphal stages, of which there are five, are the same in 

 general appearance, except that the main dorsal projections in the first 

 stage have only one subspine, while in the second and remaining stages 

 there are numerous branches. A second difference is the growth pos- 

 teriorly of the prothoracic shield and the appearance of wing pads in the 

 last three stages. These two differences, with the increase in the size of 

 the body and the general darkening of colors in each successive stage, 

 enable one to recognize any of the different stages. 



DESCRIPTION OF INDIVIDU.\L ST.^GES 



Stage I (PI. XLIII, fig. 2,0). — Length, 1.6 mm. (1.4 to 1.7 mm.), average of 10 speci- 

 mens. Head, thorax, abdomen, and all appendages pale when first bom. After 

 feeding the abdomen takes on straw color and the cologne-earth patch of the tliorax 

 becomes faintly visible. Eyes white. Twelve pairsof dorsal hairlike projections with 

 one upright spine. One pair on head, four on thorax (two on prothorax, one each on 

 mesothorax and metathorax), and seven on abdomen. Spines colorless, pale. Uody 

 regularly but sparingly covered with spines, conspicuous and large compared to size 

 of body. 



Stage II (PI. XLIII, fig. 3). — Length, 2.1 mm. (1.9 to 2.3 mm.), average of 10 speci- 

 mens. Head, thorax, abdomen, and appendages light straw colored. The cologne- 

 earth patch of the thorax becomes more pronounced and extends back onto the abdo- 

 men. Eyes in this and succeeding stages with white margin and brown center. The 

 dorsal projections have become fleshy and bear several lateral spines, the upright spine 



