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lar sense, but even by scientists, referring at one time to the true lo¬ 
custs (species of Acrididae ), and at another to the Locustidae , or 
family including the katy-dids, and the greenish species with long 
slender antennae that are found upon the higher grass, weeds and 
bushes. In fact the term, as generally used, applies to most of the 
species of these two families, the term “katy-did” including but a 
comparatively small portion of the Locustidae. 
The name “Locust” has unfortunately been applied in this country 
to an insect not even belonging to the same order as the locusts of 
oriental countries. The “seventeen-year locust” of North America is, 
in fact, not a locust, but a species of Cicada , or, as another species 
of the same group is often called, a “harvest-fly” or “dry-fly,” be¬ 
longing to the Order Uemiptera, which contains only insects with a 
mouth prolonged into a horny, jointed tube, formed for sucking the 
juices of plants; while true locusts have biting-jaws; or, as they are 
termed by the prophet Joel, “cheek-teeth.” The grasshoppers which • 
have appeared in such vast swarms and done so much mischief in the 
western states and territories are true locusts, and this term is gradu¬ 
ally coming more and more into use in the proper sense. 
Before entering upon the classification and description of our species, 
it will be best for me to explain the peculiar terms used, and the 
peculiar application of the general terms as they are used in describ¬ 
ing species and genera of Acrididae. The terms head , thorax , protho¬ 
rax, , mesothorax , metathorax , abdomen , antennae -, femur , tibia , tarsi , and 
the names of the mouth parts, are applied in the same general sense 
as in other orders, and as explained in my first report. The insect 
when described is presumed to be on its feet and the wings closed 
as represented in Fig. 10, (except, that in describing the under wings 
they are considered as spread.) The necessity for mentioning this 
fact is, that the relative terms anterior , posterior , outer , inner , upper 
and loioer. apply to the position of the insect or its parts, and unless 
these are known there will be confusion in the use of these terms. 
Anterior, before and forward, will then signify toward the front part 
of the head; posterior behind and similar terms, will signify toward the 
hind extremity of the abdomen; upward, above, toward the back, and 
the opposite terms toward the under or ventral side; lateral signifies 
toward or on the side; transverse, across the body or part described; 
and longitudinally, lengthwise of the body or part described. The 
term “transverse” is also often used to signify that the piece or part 
is broader than it is long, length always retaining the idea of the 
direction of the length of the whole insect. 
The parts of the head which need special explanation are the following: 
The clypeus , the piece in front, immediately below the face, in the 
form of a transverse parallelogram, “tucked” at the sides; when the 
face is very oblique it is really underneath, but still the face is con¬ 
sidered the front. The frontal-costa or median carina of the face, is 
the ridge which extends down the middle of the face; it is often 
grooved, when it is said to be sulcate , sulcus signifying a groove. 
Running down each side of the face there is usually a sharp ridge 
or raised line, called a lateral carina / the two forming the lateral 
carinm of the face. The top of the head, which is really the back 
of the head in Acrididae, is considered as divided into two parts by 
an imaginary line drawn across it from the hind margin of one eye 
to the hind margin of the other; the portion lying behind this line 
