Uniformity of successive populations of an alpine grasshopper with a two-year diapause.

-UNIFORMITY OF SUCCESSIVE POPULATIONS OF AN ALPINE GRASSHOPPER WITH A TWO YEAR DIAPAUSE. Aeropedellus clavatus (Thomas), an abundant grasshopper in the alpine tundra of Colorado, has a two-year diapause. This suggests the possibility of two distinct populations in successive years. Statistical analysis of samples from three alpine localities on Mount Evans, Colorado, collected in 1958, 1959, and 1960, demonstrate that samples from successive years are as much alike as are those from 1958 and 1960. Successive populations are therefore essentially uniform. Apparently all individuals do not have a two-year diapause, a few eggs hatching after only one winter while a larger number, probably, go through three winters before hatching.-Gordon Alexander, 765 14th street, Boulder, CO 80302. Descriptors: alpine, diapause, grasshopper, populations.