APHANIPTERA. 351 



groove, and are sometimes more or less covered by a chitinous 

 plate. I shall return to the structure of the antennae later on. 



The thorax consists of three distinct segments, each bearing a 

 pair of legs ; and each segment is composed of one dorsal plate 

 and two side-pieces or pleurae. There is a very small spiracle, 

 difficult to see, just at the posterior lower corner of the pleura of 

 the prothorax. Then holding a very similar position on the meso- 

 thorax there is the small, round scale, which has hitherto been 

 called a rudimentary wing, but which is really a spiracle. Then 

 at the back of the metathorax is the large flat scale, which is said 

 to represent the hind wing by all except Taschenberg, who, how- 

 ever, while denying that this is a rudimentary wing, asserts that it 

 is a portion of the metathorax. For my part I am inclined to 

 believe that it represents the first ventral plate. 



There are eight clearly defined abdominal segments ; some 

 authors say nine and some ten ; but then they probably include 

 the genital plates. Each segment consists of one dorsal and one 

 ventral plate, the former bending over the back and down on each 

 side, and contains two spiracles, and usually bears one or more rows 

 of bristles. The first dorsal plate, however, is much smaller than 

 the others, and does not contain any spiracle, the missing spiracle 

 being situated quite at the top of the so-called rudimentary wing, or, 

 according to Taschenberg, metalhoracic appendage, or, as I think, 

 first ventral plate. The fact that it bears a spiracle, two rows of 

 stiff bristles, that there is no plate beneath it^ it alone forming a 

 covering for the soft parts of the body below, is quite conclusive 

 that it cannot be a wing. Taschenberg considers that the posses- 

 sion of bristles and a stigma prevent it being a ventral segment, 

 for, he says, " the other ventral segments have no spiracle and no 

 such bristles. But then, if this is the case, I ask, " What has 

 become of the first ventral segment ?" It would only tire you if I 

 went through all my reasons for my opinion ; but very likely after 

 all I may be wrong, and I shall certainly not forget the concluding 

 lines of the Chameleoft : — 



" When next you talk of what you view. 

 Think others see as well as you : 

 Nor wonder when you find that none 

 Prefers your eyesight to his own." 



