448 CLASS INSECTA. 



from whence very considerable damage often accrues to the 

 agriculturist. The tracheae of these larvaj are elastic, while 

 those of the perfect insect are tubular. The nervous system, 

 considered in these two ages, also presents remarkable dif- 

 ferences. The ganglia are less numerous, and more approxi- 

 mating in the insect arrived at its final transformation, and 

 the two hinder ones throw out a great number of threads, 

 disposed in radii. According to the observations of M. 

 Marcel de Serres, on the eyes of insects, those of the majo- 

 rity of the lamellicornes present peculiar characters, and which 

 approximate their organization to that of the tenebriones, 

 blattae, and other lucifugous insects. 



The alimentary tube is in general very long, especially in 

 the coprophagi, folded on itself, and the chylific ventricle 

 bristles with papillas, which M. Dufour has recognized to be 

 sacs destined for the repository of the alimentary fluid. The 

 biliary vessels resemble, in their number and mode of im- 

 plantation, those of the carni^'orous coleoptera, but they arc 

 much longer, and more attenuated. 



We shall divide this family into two tribes.* 



The first, that of the ScarahocidcB) presents antennae, ter- 

 minated in a foliated knob, and plicatile in the majority, but 

 in others composed of emboxed articulations, either in the 

 form of an inverted cone, or almost globular. The mandi- 

 bles are identical, or almost similar in the two sexes, but the 

 head and corslet of the male individuals often present projec- 

 tions or peculiar forms ; sometimes also their antennae are 

 more developed. 



This tribe corresponds to the genus 



* The anatomy is, according to M. Dufour, so different, that these 

 two tribes ought to constitute two families. The sections would then be 

 tribes, and would form, some of their divisions, so many principal 

 genera. 



