September ■.S9!i.J PSYCHE. 257 



6. Cerci roughly sock-shaped by an expansion on the dorsal 

 margin of apex (Fig. 44) . Hind femora robust, not transverse- 

 ly banded with dusky. Interspace between mesosternal lobes 

 nearly twice as long as broad. A large, robust species, with 

 unspotted tegmina AT. femoratus. 



6'. Cerci terminating in a transverse, oval, tumid lobe (Fig. 45). 

 Hind femora slender, transversely banded. Interspace sub- 

 quadrate. Tegmina more or less distinctly spotted. A 

 species of medium size. .... M. punctidatus. 

 4". Cerci simple in outline, nearly straight. 

 7. Furcula very short. 



8. Cerci nearly straight, three or four times as long as their middle 

 breadth and sub-equal in width throughout (Fig. 39). 



M. /asciatus. 



8'. Cerci less than three times as long as their middle breadth, 



tapering, slightly curved dorsad (Fig. 37). . M. scudderi. 



7'. Furcula long, much longer than last dorsal segment, from which it 



arises (Fig. 40 c) . 



9. Cerci tapering, the distal half less than half as broad as the 

 extreme base (Fig. 40) . . . J/, femur-rubrum . 



9'. Cerci with the distal half distinctly more than half as broad 

 as the extreme base (Fig. 41). . . . M. extremus. 



Key to Species uf Melanoplus. — Fem.ales.^ 



I. Tegmina no longer or scarcely longer than pronotum (See note on p. 256) . 



2. Interspace between mesosternal lobes usually distinctly transverse. (Fig. 

 39a). Mid-carina of pronotum usually obsolete or rudimentary on pro- 

 zona. Lateral lobes of pronotum noticeably longitudinal, the ventral half 

 very pale in color, contrasting strongly with the dorsal half (Fig. 38a) . 

 Tegmina shorter than pronotum, sub-oval (Fig. 38b). A conspicuous 

 oblique pale streak on the metepisternum. . . M. mancus. 



2'. Interspace quadrate. Mid-carina of pronotum conspicuous, about equally 



* In using this table it should be distinctly understood that implicit reliance cannot be placed on any single character, 

 so great is the similarity between species and so wide the range of individual variation. In many cases all available 

 cliaracters need to be considered in order to determine with certainty the species to which a given specimen belongs. In 

 addition to the points stated in the table, the measurements, locality, and date may be found helpful. From 90 to 95 % of 

 the specimens examined will be readily determined by this table, most of the remainder with a little trouble, and about 2 

 or 3 % not until the student has become thoroughly familiar with all of the species here considered. Femoratus will be 

 at once recognized by its size ; puuctnlat^s by the form of the ovipositor ; mijtor, less readily, by the same means ; 7iiancus 

 and scudderihy the tegmina; but the other five will be more difficult. 



