'20 



as the disk of the elytra. The angle of the elytra is the longitudinal ridge 

 formed along the interno-inedian nerve by the sudden flexure from the hori- 

 zontal to the vertical portion when closed. 



When describing the wings they are supposed to be fully spread (Fig. 

 1, wg)* The terms disk and base are sometimes, though not properly, used 

 interchangeably, referring to the moiety of the wing next the body. At other 

 times disk is properly applied to the middle portion. I use the term sub- 

 marginal area to designate that portion between the anterior margin and 

 next strong nerve; margin, when used without any qualification, signifies the 

 front margin. The nerves, or veins, are the ribs which run from the base to 

 the outer margin, f and form the lines of plication when at rest. The nervules, 

 or veinlefs, are the minute transverse ribs running from one nerve to another. 

 When these are placed regularly like the rounds of a ladder, they are called 

 scalariform. In many species, especially of CEdijwdini, the basal half of the 

 wing is colored red, yellow, or some other bright color, which is often bounded 

 exteriorly by a black or fuscous band, extending across the face from the 

 anterior to the posterior margin, generally curving along the latter to or 

 toward the jyosterior or anal angle ; in other species the greater portion of the 

 wing is black or fuscous, while in a large number the entire wing is pellucid. 



The abdomen is the posterior part of the body which is attached to the 

 metathorax (see Fig. 1, ab). It is generally sub-convex on the under side, and 

 slightly comi)ressed laterally or sub-carinate above. It is composed of some 

 Bight or nine corneous rings or segments, which decrease in size toward the 

 apex (though in some genera, as Caloptenus and Pezotettix, the terminal seg- 

 ments of the male are somewhat enlarged). The typical number of segments 

 of the abdomen, according to Lacaze-DuthiersJ (who is followed by Dr. Pack- 

 ard in his " Guide to the Study of Insects"), is eleven. But if we count the 

 dorsal segments in the female to and including the point where the upper and 

 lower plates separate for the extrusion of the ovipositor, there are really l)ut 

 nine. It is true that the ninth, which folds over the upper valves of the 

 ovipositor, shows two transverse folds besides the terminal piece over which 

 the pre-anal plate rests ; each of these is counted as a segment by Lacaze- 



* Only the portion of the wing next the base is here shown, the apical half being 

 omitteil. 



f In Fig. 1 these appear as rays riinuing outward from the point where the abdomen 

 joins the thorax ;" those from wg back to the abdomen belong to the wiug. 



\ Ann. des. sci. nat. XVII, 1852, (recherches sur I'armure gcuitalc female dcs 

 iusectes orthopteres), 207. 



