1920] Walker: Orthopteroid Orders 139 



the very thin cuticle, associated with the cryptozoic Hfe. The 

 number of antennal segments increases with development. 

 Large prothoracic expansions are present in the nymphs of 

 some species. 



A few species of Isoptera are inquilines in the nests of other 

 species of the same order. 



Zoraptera. Inquilines in the nests of certain Isoptera; life 

 cycle unknown. 



Grylloblattoidea. The single species is alpine, living under 

 stones and on snow; carnivorous (has been fed on ant pupae); 

 metamorphosis practically confined to the genitalia; styli 

 present except in adult female. Hibernating as nymph or adult. 



Phasmoidea. Phytophagous, generally on trees and bushes; 

 voracious and reaching in some species an enormous size. Eggs 

 few (12-100), each in a separate seed-like capsule, dropped at 

 random. Incubation period sometimes extending over two 

 years. Period of growth variable, 6 weeks to 16 months; num- 

 ber of moults few, variable, two or three in known cases. 

 Nymphs usually not differing much from adults. 



Orthoptera. Diurnal or nocturnal ; arboreal to subterranean ; 

 phytophagous or partly carnivorous. Eggs moderately numer- 

 ous, buried in plant tissues or in the ground by an ovipositor 

 (except in subterranean forms); in the Acrididas imbedded in a 

 vesicular ootheca. Incubation period generally over winter 

 in temperate climates, comparatively few species hibernating 

 as nymphs or adults. Generally one brood, moults 4 to 6. An 

 inversion of the wings takes place at about the fourth moult, 

 the hind wings overlapping the front, until the final ecdysis, 

 when the normal position is restored and the hind wings folded. 

 Otherwise the nymphs are usually lacking in special modifica- 

 tions, though the color pattern is sometimes distinctive. 



Dermaptera. Carnivorous and phytophagous; eggs dropped 

 at random but sometimes picked up afterwards by female and 

 carried to places of safety; in Forficula auricularia deposited 

 in early spring; period of growth in this species about 5 weeks; 

 moults 3 or 4. One or two broods, hibernating at various 

 stages. Special form changes: Increase in the number of 

 antennal segments ; cerci of a few primitive genera segmented in 

 the nymphal stages. 



The aberrant African genus Hemimerus, parasitic on rodents, 

 is viviparous. 



