\ 



SUB-PHYLUM III 



INSKCTA 



083 



Fl... 1441. 

 '* nrticorn.il, Koch and 



To this lowly organised class of insects belong th.- Thytanura und < U-mbola 

 (Spring-tails). Brongniart describes I uj> from th<- Carbop- 



iferous of Conimentry (Dasypeltus Lucari), \\hi.-li 

 resembles tlie living Lepisma, but has only a single 

 terminal filanu-nt. In amber and the. Oiigocene of 

 Florissant ;i numlx-i- of species are found, some of 

 which belong to still living, and others to extinct 



genera. Examples: PetroUus (Fig. 1441), Lepidion, g" * m **- 



Forbicina, Machilis, etc. Planocephalus, a headless 



form from the Oligocene of Colorado, is regarded by Scudder as the type of a di.-tim-i 

 sub-order. 



Order 2. ORTHOPTERA. 



Fore wings coriaceous, hind wings thinner, delicately veined, plicated. The five 

 principal veins of the wings, with all their branches, extend to the outer margin <>f ih? 

 wing. Jaws adapted for biting. Metamorphosis incomplete. 



Palaeozoic representatives of this order frequently combine characters which are at 

 present distributed among different families. The neuration of their wings also shows 



FIG. 1442. 



Palaeoblattina Douvillei, 

 Brongt. Silurian ; Jnrques, 

 Calvados. 2/ 3 (after Brongniart). 



Fio. 1443. 

 Aedoeophasma Anglica, Scudder. Coal Measures ; England. 1/1- 



a less marked differentiation than is the case in more recent Orthoptera ; moreover, 

 the fore and hind wings differ less decidedly from each other than in the later form-. 



An isolated wing from the Middle Silurian of Jurques, Calvados (PalaeobUtt'tn>t 

 Douvillei, Brngt., Fig. 1442), is one of the oldest of fossil insect remains, but does not 

 admit of closer determination ; Brongniart no longer regards it as a cockroach. The 

 Carboniferous of North America and Europe yields numerous genera and species, 



which are more or less closely related to typical 

 Orthoptera. Some of these are of gigantic propor- 

 tions. The richest localities for remains of this 

 order are Commentry, France ; Saarbriicken and 

 Halle, Germany ; Illinois ; Ohio ; and West Virginia. 

 Many genera are known only by detached wings. 

 Among the largest and best preserved forms are 

 Protophasma, Stenoneura, Aedoeophasma (Fig. 1443), 

 and Paolia. Smaller forms include Polioptentu 

 (Fig. 1444); Oedischia with saltatorial hind legs; Stethaneura, Caloneura, and 

 Ischnoneura. Cockroaches, however, were the prevailing type during the Palaeozoic, 

 fully 200 species being known, belonging to the genera Etoblattina, Gerablattina, 

 Anthracoblattina, Progonoblattina (Fig. 1445), Mylacris, etc. Spiloblattina from tin- 

 Trias is placed in the same group as the Palaeozoic forms, under the name of Palaeo- 



Polioptenus elegans, Goldenbg. sp. Coal 

 Measures ; Saarbrucken, Germany. Vi- 



