EMBIOPTERA. 683 



with the fact that they require a certain amount of heat and 

 moisture. When removed from their retreats to the outer air, 

 except during the swarming flight, they soon die. 

 Taere is a single family : 



Fam. 1. Termitidae. With the characters of the Order. There are- 

 about one hundred described species, but it is thought that many await 

 description and that there may be some thousand in all. Termes has 

 representatives in all the warmer parts of the globe, often very 

 destructive in their habits. The woodwork of the Imperial greenhouses 

 at Schonbrunn, Vienna, was completely eaten away a few years ago by 

 T. ravipes, a species which in both worlds attains a high northern limit 

 for a termite. Eutermes, with several American species, often inhabits the 

 nests of Anoplotermes, a form in which the soldier grade does not develop. 

 Hodotermes * is thought to produce no winged forms ; it is at any rate in 

 some species a harvesting form, collecting both grass and leaves. Calo - 

 termes has already been described. 



Order 10. EMBIOPTERA f (EMBIIDAE). 



Small insects with rather drawn-out bodies ; pro-thorax small, but 

 meso- and meta-thorax elongate ; with jour similar wings or none ; 

 three or jour longitudinal and a few transverse nervures. Not social. 



This is a very small order with some twenty described species. 

 They inhabit warm climates, are unattractive, and have received 

 little attention. The antennae have from fifteen to twenty-four 

 segments. The coxae are separate, the tarsi three- segmented, 

 the abdomen has ten segments and carries a pair of two-segmented 

 cerci. The proximal segment of the anterior tarsus gives exit 

 to the secretion of a gland which hardens into silk, with which 

 tunnel-like webs are woven under stones, where the insects 

 live in a warm, moist atmosphere. Their food is vegetable. 



There is but one family : 



Fam. 1. Embiidae. With the characters of the Order. Oligotoma is 

 Indian and Pacific and has been introduced into England. Embia 

 Mediterranean. 



Order 11. EPHEMEROPTERA J (EPHEMERIDAE). 

 Fragile insects with poorly developed mouth-parts, the imago 



* P. Boston Soc., xi, 1868, p. 399. 



t Hagen, Canadian Entomologist, xvii, 1885, Grassi, Ace. Gioen, vii, 1889. 



% Pictet, Hist. Nat. Neuropt., Ephemerines, 1843. Lubbock, Tr. Linn. 

 Soc. Zool. xxiv, p. 61. Vaysierre, Ann. Sci. Nat. Zool. (7), ix, 1890, 

 p. 19. Ronalds, Fly-Fisher's Entomology, 4th ed., 1849. Eaton, Mono- 

 graph of the May FHes, Trans. Linn. Soc. (2), iii, p. 1, 1888. 



