I 84 APTERA 



CHAP. 



briefly reviewed some of the external characters of the other 

 Thysanura. 



The second family (Japygidae) consists of one genus Japyx, of 

 which there are, no doubt, several different species in various 

 parts of the world, such having already been detected in tropical 

 Africa, in Malasia, and in Mexico, as well as in Madeira and 

 Europe. The commoner species of the latter continent, Ja'pyx 

 solifugus, lives in moss or in shady places on the edges of woods. 

 It possesses a great resemblance to a newly-hatched earwig, and 

 the writer has found it in France under a stone in company with 

 a number of the tiny creatures it was so much like. This species 

 has been found as far north as Paris, but has not been met with 

 in Britain. The family Japygidae is, like the Campodeidae, 

 entotrophous, and is distinguished by the body being terminated 

 behind by a pair of forceps instead of antennary organs. 



The other two families of Thysanura, Machilidae and Lepis- 

 midae, are ectotrophous that is, the parts of the mouth are not 

 buried in the head, but are arranged in the fashion usual in 

 mandibulate Insects. 



Only one genus of Machilidae is known, but it is no doubt 

 very numerous in species, and probably is distributed over 

 most of the globe. Machilis maritima is common in some 

 places on the coast of England. Another species (If. jpolypoda) 

 occurs amongst dead leaves in the New Forest, and we have also 

 observed a species of the genus under the loose stones that 

 frequently form the tops of the " dykes " or piled walls in Scotland. 

 In more southern Europe species of Machilis are commonly met 

 with on the perpendicular faces of very large stones or rocks, 

 over which they glide with wonderful facility. The scales on 

 the bodies of these rock-inhabiting species form pretty patterns, 

 but are detached with such facility that it is almost impossible 

 to obtain specimens in satisfactory condition for examination. 



In Machilidae ;the dorsal plates of the hind body are reflexed 

 to the under surface so as to form an imbrication covering the 

 sides of the ventral plates, and the eyes are largely developed ; 

 by which characters the family is distinguished from the 

 Lepismidae. The pair of large compound eyes (Fig. 9 2, 0) is a 

 ^remarkable feature, being indeed unique in the Aptera. The 

 structures (o, o') that Oudemans considers to be simple eyes have, 

 in external appearance, a resemblance to the fenestrae of the 



