ANIMAL KINGDOM. 285 



true saltus in nature, when on looking at the Coleopte- 

 rous insects generally, and on dividing them into five na- 

 tural groups taken from their general appearance, and 

 their manner of living, I endeavoured to discover some 

 distinct character for each. For some time I failed in the; 

 object of my Avishes ; but Bonnet's unsuccessful attempt 

 to arrange insects by their larvse happening to occur 

 to me, I perceived on examining my groups that the, 

 larvae of all of them were very distinct from each other 

 in point of appearance. Of the fifth group indeed I could 

 form but little judgemefnt, as the larvse of it were but very 

 imperfectly known ; but in the other four were to be 

 discerned Scolopendriform larvse, Juliform larvjB, Apod or 

 Vermiform larvae, ahd active Hesapod larvae. The ana^ 

 togy was Evident; and I Was thus immediately led to con-; 

 elude that there was an error in the degree of importance 

 which ill the above classical division of the Annulosa had 

 been given to the /^er»i«s.'"i ~"f5.;i) Vui;fa ,,/,/, i ..:•;] 

 'M. Riiddlphi in Ms ex/cellent work bri ttee; JEwioroa found 

 it necessary to make two great sections of them, which 

 have by succeeding wrlters^beert elevjaied to the rank of 

 classes on accdtlnt of th© vast diflferenee between their re- 

 speetive or'ganizationsl No#i thMwihen thus contrasted 

 wittvohe another they ought to form separate classes will 

 hot admit of dbubt^ a§ We' shall see; by the following state- 

 jn'ent. One of these sections is composed of intestinal 

 worms, without any 'distinct organs, animals whose exist- 

 ence is only proved by the irritability of their soft vesicu- 

 lar substance. The other on the contrary consists of such 

 as are furnished with a nervous system formed by two 

 longitudinal threads terminating in a medullary coUar,-*- 

 wonrts, in short, which have two apertures to their vor 



