NO. 1G87. THt: THORAX OF lS^K("IX—tiNOTHiRAt<^. 559 



anatomical stnictiiro and relation to the surroundino- parts are dif- 

 ferent. Therefore, why not call one a part of the abdomen, which it 

 actually is, and the other a part of the thorax, which it actually is? 



(). AA^ing articulation of typical generalized tj'pe, generally four 

 axillary sclerites present, bases of the veins mostly distinct (GO-GO, 

 185-189). 



In some cases the first axillary is divided into two as in Locustida? 

 {Mki'occntriim laurifoUum, G3, G4). Voss (1905) describes the same 

 thing in Gvyllus domesticus. In G. pennsylvanicm the neck of the 

 first axillary is joined to the body of the sclerite by very delicate 

 chitin, but the two parts can be demonstrated to be continuous (188). 



The venation presents many modifications, but each form possesses 

 some character which, used in strict conformity in all the families, 

 furnishes a clue for the identification of the veins. (See Plates 47, 

 48, G5.) An important character is the location of the first anal 

 fold {AF) in which the vena dividens {D) is located wdien the 

 latter is present (58, 09, 185, 18G, 189, D). It will be noticed that in 

 all cases, except in the fore wing of GryJlus (07) the first anal vein 

 {lA) lies in front of the anal fold {AF) or the vena dividens {!)) 

 and is independent of the rest of the anals at the base. That this is 

 a nymphal condition is shown by the nymphal Mantid wing (59). 

 Comstock and Needham (1898, '99) have illustrated the same thing 

 in the wing of a young cockroach. Thus the first anal vein can be 

 identified by its lying before the first anal fold and by its basal 

 independence. Likewise its absence can be proved in the fore wing of 

 Gryllus 07. The anal fold here appears to lie before the cubitus 

 {Cu) but basally it will be found originating behind this vein. In 

 the hind wing of the same species (GO) the anal fold and first anal 

 are normal. The first anal is frequently branched (00, 04), while in 

 Dissosteira it fuses basally with what appears to be the vena dividens 

 of the hind wing (09, 189). 



The cubitus {Oii) and media {M) show a tendency to unite Avith 

 each other at their bases, as illustrated in Blattida3 (00), Mantida) 

 (G2), Locustida* (03, 04), Gryllida^ (G7), and Acridiida) (08, 187). 

 In the hind wings of GryUun (GO) aii^^ Dissosteira (09) the media 

 (J/) is fused for some distance with the radius (i?). That the vein 

 labeled M is the media in these wings can be determined by compari- 

 son with the venation of the fore wings (07, 08), where the media is 

 separate from the radius at least to a point proximal to its union with 

 the cubitus. In the fore wing of the Acridiid?e {Dissosteria G8) the 

 costa (6^) forms the anterior margin, while the subcosta {Se) is 

 clearly double from near the base. It is, hence, clear that in the hind 

 wing the costa is absent and that what is here the marginal vein is the 

 first branch of the subcosta " {Sc) . 



