330 PTILOTA. 



7. Aptera. — Wings, none. (Spiders, crabs, centipedes, 

 lice, tleas, &c.) 



The incongruous nature of this last-named order has been 

 abeady commented upon. The names of these orders are 

 compounded from the Greek word irrepov (pteron), a wing, 

 in conjunction with some other prefixed to it. We have 

 thus Coleoptera, sheath, or case-winged; Neuroptera, nerve- 

 winged, &c. 



It soon, however, became evident that the characters of 

 the wings were too general, and Fabricius, a disciple of Lin- 

 naeus, fell into the opposite error of regarding the variations 

 of the mouth as alone aflPording the most satisfactory distri- 

 bution of insects. In the system of the last-named author, 

 a number of new orders (or, as he chooses to term them, 

 classes) were established, and to which, in addition to such 

 of the Linnsean orders as he retained, he gave a series of ex- 

 ceedingly harsh names, founded upon the structure of the 

 mouth ; dividing the orders into two primary groups, founded 

 upon the masticatory or suctorial habits of the insects. 



But, as the Linnsean system, founded upon the wings, was 

 found to violate natm-e by uniting masticating and suctorial 

 insects in the same order, so the Fabrician system was, in 

 some respects, even more artificial, as where the wingless 

 sugar-lice (Lepisma), which undergo no metamorphosis, were 

 introduced amongst the metamorphotic lace-winged flies, &c. ; 

 and the lice and octapod mites {Acari), were united with the 

 two-winged flies {Diptera), into the class Antliata. The 

 system of Fabricius has met with but few followers, except 

 in Germany ; his chief merit consisting in his definition of a 

 great midtitude of new species. 



It is to the labours of the French naturalists, Cuvier, La- 

 marck, and Latreille, and to our venerable Kirby, that we 

 are mainly indebted for the great advances made towards a 

 more natural mode of distribution, wherein the natural 



