208 FAMILY VI. ACRIDIM3. THE LOCUSTS. 



c. Apical spurs on inner side of hind tibiae very unequal in length, 

 the middle one sometimes twice as long as the others; occiput 

 and often the disk of pronotum with supplementary carinse. 

 d. Antennae depressed and somewhat clavate toward apex (Fig. 

 83, h) ; tegmina as long as the abdomen; lateral carinae 

 subparallel. II. EKITETTIX. 



del. Antennae depressed toward base and narrowed toward apex, 

 which is blunt; tegmina shorter than abdomen; lateral 

 carinee much curved inward at middle. III. PEDETICUM. 

 cc. Apical spurs on inner side of hind tibiae subequal; occiput and 

 pronotum without supplementary carinae; all carinse of pro- 

 notum cut much behind the middle by the principal sulcus; 

 antennae of male twice or more the length of pronotum, their 

 basal halves strongly flattened. IV. CHLCEALTIS. 



bb. Disk of pronotum with lateral carinse, when present, strictly 



parallel or diverging very slightly on the metazona. 

 e. Head and thorax striped with brown; scapular area of tegmina 

 dilated, subhyaline; pronotum with lateral carina? very faint 

 or wanting; supplementary carinse usually present in female; 

 smaller, female not over 22 mm. in length. V. AMPIIITORXUS. 

 ee. Color uniform brown or grayish-brown; scapular area of teg- 

 mina not dilated, opaque; lateral carinse of pronotum evi- 

 dent; supplementary carinse wanting; larger, female 27 or 

 more mm. in length. VI. AMBLYTROPIDIA. 



I. SYRBULA Stal, 1873, 90, 102. 



Head nearly, female, or fully, male, as long as pronotum; oc- 

 ciput moderately rounded and feebly ascending; vertex subtrian- 

 gular, its sides rather prominent, median carina distinct, front 

 margin subangulate, deflexed and rounded into the frontal costa ; 

 antennae filiform, flattened toward base, expanded apically in the 

 male; frontal costa wide, narrowed at apex, deeply sulcate, male, 

 feebly so, female; pronotum. with the three carina? distinct, the 

 lateral gently or strongly sinuate, so that the disk is plainly nar- 

 rower at middle, all cut by one sulcus slightly behind middle; 

 lateral lobes of pronotum about as high as long, their front and 

 hind margins moderately oblique, the latter slightly sinuate, the 

 lower margin more or less undulate; tegmina well developed, 

 equalling or slightly exceeding the abdomen in both sexes, those 

 of male distinctly, regularly reticulate except in the anal and 

 scapular areas, which are widened, those of female feebly reticu- 

 late and not expanded in the areas mentioned; hind femora un- 

 usually long and slender, surpassing the tips of tegmina in our 

 species; subgenital plate of male acutely conical, not longer than 

 the preceding segment; ovipositor moderately exserted. 



