ORDER ORTHOPTERA. 
Non-saltatorial Orthoptera. 
This group comprises three families which have received as 
many different group-names in allusion to their different modes of 
progression or the special adaptations shown by the legs : 
Cursoria, — running Orthoptera, Family Blattidae, Cockroaches. 
Ambulatoria, or Gressoria, — walking Orthoptera, comprising 
the Family Phasmidae, Walking-sticks, and the Family 
Mantidae, Praying Mantes or Mantids. The latter family 
has also been termed 
Raptoria, — from the predatory habits and the special modifica- 
tion of the front legs for seizing prey. 
COCKROACHES— Family BLATTIDAE. 
Body strongly depressed, more or less oval. Antennae long, 
bristle-like. Head concealed beneath the pronotum, the face 
ventral, the mouth posterior. Coxae long and free; legs slender, 
similar, compressed, the femoro-tibial joint moving in a hori- 
zontal plane. When fully developed, the tegmina are parch- 
ment-like and overlapping, and the wings membranous, with 
large anal area; both tegmina and wings are often rudimentary or 
wanting in the female and sometimes in both sexes. 
Cockroaches are prevailingly tropical in distribution, needing 
heat and moisture, and only three native species are thus far 
known to inhabit New England, The group appeared very 
early in geologic time, some representatives as early as the middle 
Silurian and many in the Carboniferous Age. In all, over 130 
species have been described from the Palaeozoic rocks of the 
United States. Consequently it is a group of great interest to the 
student of insect palaeontology. " Of no other type of insect can 
it be said that it occurs at every horizon where insects have been 
found in any numbers; in no group whatever can the changes 
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