FAMILY v.— ACRIDIIN^. 193 



owing to the large numbers of parasites which soon become 

 so numerous as to ahnost annihilate their host. ' This insect 

 is single brooded in Minnesota. Its life-history, with illus« 

 tration, is given elsewhere. 



Melanoplus spretus Uhler. 



THE ROCKY-MOUNTAIN MIGRATORY LOCUST. 



Of large size, but of slender form, light griseo-fuscous, 

 more or less cinereous, and often tinged to a greater or less 

 degree with ferruginous. Head somewhat prominent, light 

 fusco-olivaceous, with a broad, piceous, post-ocular band, 

 and above more or less infuscated or dulled in color, often 

 with a pair of longitudinal fuscous stripes; vertex rather 

 tumid, raised considerably above the level of the pronotum ; 

 fastigium steeply declivent, rather deeply (male) or shal- 

 lowlv (female) sulcate throughout; frontal costa moderately 

 prominent, distinctly failing to reach the clypeus; ej-^es not 

 very large nor very prominent. Pronotum very short, equal 

 on the prozona, expanding somewhat on the metazona, 

 light brownish fuscous, often ferruginous, the lateral lobes 

 with a much broken and maculate post-ocular piceous or 

 dark fuscous band confluent to the prozona, the disk broadly 

 convex, passing into the vertical lateral lobes by a rounded 

 angle forming a blunt shoulder on the metazona and poste^ 

 rior section of the prozona only; median carina distinct on 

 the metazona, feeble and often sub-obsolete on the prozona. 

 Prosternal spine rather long, appressed, feebly conical, very 

 blunt, erect, shorter in the female 

 than in the male. Tegmina except- 

 ionally long, far surpassing the hind 

 femora, not very narrow, sub-equal, 

 brownish testaceous, heavily flecked 

 w4th blackish fuscous, usually 

 through the discoidal area but 

 sometimes confined to the middle Fig. 119.- Meianopiusispre, 



!• • 1 1 1- ,1 t US, tip of TO ale a bd o tn ea. s'Orig. 



line; wings ample, hyaline, the inai. * 



