304 



KELLOGG AND BELL 



In Scudder's Monograph of the Melanoplinae (1899) 129 

 species of Melanoplus are described, for 127 of which the num- 

 ber of tibial spines in the outer row is used as a specific charac- 

 ter, certain variation within definite limits being ascribed to most 



to al 



FIG. 66. Frequency polygon of the variation in number of spines in outer 

 row of right tibiae of 47 female red-legged locusts, Melanoplns femur-rubrum. 



of the species. The number ascribed to Jemur-rubrum is " 10 to 

 13, usually ii." The range, in males alone, of our short series 

 covers all the typical numbers of spines (outer row) recorded and 



rff 



FIG. 67. Frequency polygon of the variation in number of spines in outer 

 row of left tibiae of 48 female red-legged locusts, Melanoplus femur-rubrum. 



used diagnostically for all the species in Scudder's Monograph. 

 There are no discernible marked differences between males 

 and females in the extent and character of the variations. 



