216 INSECTS. 



XI. GLOSSATA. Mouth with a spiral tongue, reflexed be- 

 tween the palpi. 



XII. RHYNGOTA. Mouth with a rostrum and articulated 

 sheath. 



XIII. ANTLIATA. Mouth with an inarticulate haustellum, 



Subsequent writers have proposed various systems, combining 

 the characters of Linnaeus and Fabricius. The most promi- 

 nent of these is that by P. A. Latreille, who, in 1796, in his 

 Precis des caracteres generiques des Insectes, limited the de- 

 finition of the class, and whose object in his subsequent writings 

 has been to divide his orders into natural groups. Cuvier, La- 

 marck, and others have also done much to increase the anato- 

 mical and general knowledge of Insects, and to facilitate their 

 study by appropriate arrangements ; and our own countryman, 

 Mr Macleay, has suggested a very ingenious classification, found- 

 ed on the quinary system, by which it appears that the groups, 

 when arranged in circles of five, seem mutually connected toge- 

 ther. The Annulose animals in this arrangement form a sub- 

 kingdom, thus, supposing the words to be placed in five con- 

 nected circles : 



AMETABOLIA. 

 CRUSTACEA. MANDIBULATA. 



ANNULOSA. 

 ARACHNIDA. HAUSTELLATA. 



The great branches of the Annulosa are in the same manner 

 subdivided into quinary circles, of which the following is an ex- 

 ample. 



HYMENOPTERA. 

 COLEOPTERA. TRICHOPTERA. 



MANDIBULATA. 

 ORTHOPTERA. NEUKOPTERA. 



Each of these groups is farther subdivided into five families; and 

 Mr Macleay has besides stated every circle to be resolvable in- 

 to two superior groups, which he denominates normal or typi- 

 cal, and three inferior ones, which he terms aberrant or annec- 

 tant. 



Other systems have at various periods been proposed by 



