Dermaptera Thysanoptera. 15 



ORDER DERMAPTERA. 

 (EUPLEXOPTERA; EUDERMAPTERA.) 



Elongate, but small insects with the abdomen terminating in a 

 pair of strong movable forceps. Fore wings horny, but short, hind 

 wings large, nearly circular, radially folded from near the center 

 (PI. 1, fig. 18), when folded, projecting slightly beyond the upper 

 pair; mouth mandibulate; antennae long and slender. Metamor- 

 phosis incomplete. Earwigs. 



1. Metapygidium and telson not reduced, nearly as large as the pygidium which 



is relatively small; head depressed, truncate or concave posteriorly; femora 

 compressed and usually keeled; tropical earwigs. (Pyragra, Pyragr6psis.) 



(PI. 1, fig. 15.) PYGEDICRANIIXflE 



Metapygidium and telson much reduced, very greatly smaller than the pygidium 

 which is relatively very large and sometimes with complex processes 2 



2. Metapygidium and telson although reduced in size, still present as distinct 



plates, if sometimes lost in the pygidium, the latter is fused with the last 

 dorsal segment to form a horizontal squamopygidium; femora not com- 

 pressed or keeled; head gently convex. (Anisolabis, Labidura.) (PI. 



1, fig. 17.) LABIDURIDjE 



Metapygidium not distinct; pygidium well developed, often provided with com- 

 plex processes 3 



3. Second joint of tarsi simple, not lobed nor dilated. (Labia, Prolabia.) 



LABUDM 



Second joint of tarsi with a dilated lobe on each side. (Forficula, D6ru.) (PI. 

 1. fig. 16.) FORFICULIIX& 



ORDER THYSANOPTERA. 



(PHYSOPODA.) 



Small or minute, slender species with the wings often absent or 

 reduced in size, feeding usually on plant sap. Head vertical, 

 free; eyes well developed; usually three ocelli; mouthparts fitted 

 for sucking, inferior, frequently asy metrical; pro thorax free; 

 wings, when present, very narrow, usually with long marginal 

 fringes, the venation greatly reduced; legs similar, tarsi one- or 

 two-jointed, with a bladder-like or hoof -like enlargement at tip; 

 no cerci. Metamorphosis gradual, the young very similar to 

 the adult. 



1. Female with a saw-like ovipositor (PI. 2, fig. 31); last segment of female abdo- 

 men conical, that of the male broadly rounded; wings usually present, the 

 fore pair strongest, usually with more or less well developed veins and 



