Abstract
Morphometric analysis of 16 body measurements of migratory and solitary Melanoplus sanguinipes (F.) and M. spretus (Walsh) was used to determine if M. spretus was, in fact, the migratory phase of M. sanguinipes. Migratory M. sanguinipes was found to be more similar to its own solitary phase than to M. spretus. Melanoplus spretus resembled migratory M. sanguinipes, but in 14 comparisons M. spretus differed significantly from both solitary and migratory M. sanguinipes. Despite the potential for environmental variation obscuring differences in morphology, the divergent morphometric characters of M. spretus and the phases of M. sanguinipes appear to justify the status of M. spretus as a true species.