148 



INTRODUCTION TO ZOOLOGY. 



APTERA.* 



UNDER this term numerous insects, and tribes allied to insects, 

 have, since the time of Aristotle, been artificially grouped 

 together, the common bond of union being their agreement in 

 the negative character derived from the absence of wings. 

 The Linnsean order Aptera is subdivided by modern entomo- 

 logists into four orders. 



I. MYRIAPODA. Insects which are possessed of numerous 

 feet, such as the Centipede and the Millepede, belong to this 

 order. The Centipede (Scolopendra, Fig. 1 39) is carnivorous 



Fig. 138. SCOLOPENDRA. 



in its habits, an infuses a poisonous secretion into the wound 

 inflicted by its mandibles. Some of the foreign species of 

 Centipede are above a foot in length, and proportionately 

 formidable. The Millepede (Julus, Fig. 139) feeds principally 

 on decaying vegetable matter, and is frequently found under 

 the bark of trees, coiled up like the mainspring of a watch. 



II. THYSANOURA (fringed-tail). In this order there is great 

 diversity of structure ; but the peculiarity whence the name 

 of the order is derived, will be understood by reference to 



* Without wings. The Crustacea and Arachnida, which now con- 

 stitute distinct classes, were formerly included in this order. 



