426 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
genera {Pseudopomala, Mecostethus) it is noticeably protuberant. 
The pronotum usually presents a flattened dorsal surface bounded 
by distinct lateral carinae, the median carina is but little devel- 
oped, never crest-like, the prozone often exceeds the metazone in 
length and sometimes equals it in width. The tegmina and wings 
are often abbreviated, but are very variable and sometimes are 
of full length in the same species in which they are customarily 
short. The tarsal pulvilli are large, perhaps in correlation with 
the habit of perching on plants. 
These Locusts are usually of medium size, of graceful, often 
slender, proportions, and attractive appearance. The colora- 
tion is usually highly protective in character, typically matching 
the green, brown, and gra}^ of the plant background. It may be 
either uniform or conspicuously varied with darker and lighter 
spots and streaks, and occasionally presents brighter hues. The 
wings are transparent. 
The characters most valuable and most used in distinguishing 
the species and genera are those drawn from the form of the head 
and pronotum, the venation of the tegmina, and to a less extent 
the form of the antennae and subgenital plate and ovipositor. 
Their flight is silent except for a slight rustling of the wings, 
but most, probably all, of our species stridulate when at rest by 
scraping the inner side of the hind thighs against the tegmina. 
The rasp which sets the tegmina in vibration is borne sometimes 
by the femur, sometimes by the tegmen, and varies in character 
and extent with the species. 
These Locusts inhabit by preference open grassy lands heav- 
ily clothed with vegetation, upon which they feed and typically 
perch when at rest, instead of on the ground like the Band- 
winged (Oedipodinae) and Pygmy Locusts ( Acrydiinae) . While 
several species are more abundant in dry upland fields, others are 
to be found only in damp meadows and even wet bogs and marshes 
where the soil is always saturated with water and completely 
submerged at times. 
None of our species has attracted particular attention as an 
agricultural pest, but three or four which occur locally in great 
abundance in pastures and mowing-lands must consume a very 
large quantity of feed and appreciably diminish the amount 
available for stock. 
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