190 



COLLEMBOLA 



not have the result of taking the creatiu-e into concealment, and 

 in such circumstances they may be rapidly and frequently 

 repeated until the Insect feels itself, as we may suppose, in a 

 position of safety. Three families may be very readily dis- 

 tiuguished, viz. (1) Lipuridae, in which no leaping apparatus is 

 present ; (2) Poduridae, a leaping apparatus exists near the ex- 

 tremity of the abdomen ; the body is subcylindric and evidently 

 segmented; (3) Smynthuridae, a leaping apparatus exists: the 

 body is sub-globular with comparatively large head and abdomen, 

 the intervening thoracic region being small ; the segmentation of 

 the body is obscure. 



The study of the Collembola is much less advanced than that 

 of the Thysanmra, comparatively little having been added to our 

 knowledge of the group since Lubbock's monograph of the 

 British forms was published by the Eay Society in 1873. "Why 

 the Collembola should be neglected when the Thysanura attract 

 so much attention is as inexplicable as many other fashions are. 



The family Lipuridae consists of a few very small and obscure 

 Insects of soft consistence. They move slowly, and, owing to the 

 absence of any leaping power, attract atten- 

 tion less readily than the other Collembola 

 do. Two genera are generally recognised, 

 and they should probably form separate 

 families ; indeed, in Lubbock's arrangement- 

 they do so. In one of the genera {Anoura) 

 the mouth is very imperfect, no mandibles 

 or maxillae having been detected, while in 

 the other genus {Lipura) these organs exist. 

 In the members of the family Poduridae, 

 the Degeeriidae of Lubbock, a 

 saltatory apparatus is present in the form 

 of appendages attached to the fifth abdomi- 

 nal segment (Degeeriides), or to the fourth 

 (Podurides). These appendages are during 

 life flexed beneath the body, but in dead 

 specimens usually project backwards, having 

 the appearance of a bifid tail. Poduridae are of elongate form, 

 somewhat like small caterpillars, and are frequently prettily 

 marked with variegate colours. Fig. 97 represents an arctic form 

 closely allied to our native genus Isotoma. 



I 



including 



Fig. 96. — Lipura bur 

 meisteri. (After Lub 

 bock. ) 



