10 INTEODUCTORY EEMAEKS. 



Fifthly. That each group in a circle is analogically represented 

 by the corresponding group in other circles. 



Sixthly. The arrangement which Mr. Macleay has made of a 

 class of annulose animals, designated Ametabola in his System ; 

 and its application in the present work.* 



Ametabola. — This Class, when first defined and introduced into 

 the system by Dr. Leach, consisted of two divisions only, — Thysanura 

 and Anoplura ; to these Mr. Macleay has added the two divisions 

 of Myriapoda, namely Chilopoda and Chilognatha, and also Vermes, 

 as defined by him, Horae Entom. p. 286. The Class, therefore, 

 consists of the following Orders : — Vermes, Anoplura, Thysanura, 

 Chilopoda, and Chilognatha. 



The researches and inquiries which led Mr. Macleay to this 

 arrangement, are detailed in the same work, in pp. 286-7, &c. 

 They are founded on a very careful study of the character of these 

 animals, with reference especially to recent accurate analyses and 

 descriptions of Messrs. Savigny, Latreille, and Lamarck, and they 

 afibrd a favourable example of the method pursued by Mr. Macleay 

 in his inquiries. 



I have now, very briefly, to state the application which Mr. 

 Macleay has made of the several divisions of the class Ametabola, 

 in an analogical point of view, to the larva) of Coleopterous Insects. 



In the seventh chapter, treating of the tribes of Mandibulata, he 

 gives an explanation, of which the following is the substance. — 

 " When reviewing the Coleoptera with a view to a natural division, 

 I first threw the whole into those great natural groups which 

 occurred to my sight, and, prosecuting my inquiries, at length, when 



formare, qnas analogis jungantur, sed invicem connexa esse, quasi annulum 

 annulo. Naturam non facere saltum, est adagium Linnjeanum ; multuin autem 

 abest, huncce nexum in omnibus partibus esse indicatum. Illud vero vinculum 

 extricare videtur scopus, in quem omnes perquisitiones in Historia Naturali 

 debeant attendere, ut inde pateat in creatis et consensus et ordo et sapientia, 

 si talis prjE humanis excellentia humanis verbis exprimi possit. In hoc pro- 

 positum CI. Macleay Horas Entomolorjicas conscripsit ; eximio hocce in opere 

 invenimus filum Ariadneum, quo ulterius persequcndo, viam illo in labyrintho 

 invenire possunms. Formas nempe in circulis in se redeuntibus disponere conatus 

 est ; circularis ilia dispositio nobis videtur naturaj maxime conveniens." 



* Mr. Macleay's four other primary divisions of the Annulosa being the Crus- 

 tacea, Arachnida, Mandibulated, and Ilanstellated insects. 



