41 



CHAPTEK VIII. 



ON THE SECTIONS AND FAMILIES OF THE COLEOPTERA. 



As an order, the Coleoptera are generally placed at the 

 head of the Insecta, owing to their highly developed 

 organs, complete metamorphosis, and great number of 

 species ; some idea of which may be obtained from the 

 fact that in Great Britain alone there are about 3000, 

 to which additions are steadily being made. 



Many systems of classification have been propounded 

 for them, based upon all imaginable points of structure, 

 etc., but perhaps that most usually adopted, under 

 various modifications, is founded on the number of 

 joints of the tarsi ; thus many allied families, the most 

 fully developed, possessing five joints to all the tarsi, 

 have been termed the Pentamera ; those with five joints 

 to the front and middle legs, and only four to the 

 hinder, Heteromera ; those with apparently only four to 

 all the tarsi, Tetramera ; and those with apparently only 

 three to all the tarsi, Trimera. 



This arrangement, although well marked, and in 

 most cases apparently natural, cannot be strictly ad- 

 hered to; as in the first section there are numerous 

 species not possessing five joints to all the tarsi, and in 

 the two last there is really a small joint at the articula- 



