THE COLEOPTERA. 26/ 



the Other by attributhig to certain forms higher or lower positions 

 in the insect scale. 



Formerly it was attempted, and it was supposed very satisfac- 

 torily, to divide all the Colcoptera into four great primary divisions, 

 according to the particular number of the joints of the tarsi. 

 Geofifry, a great entomologist of the last century, invented this 

 method of classification, which, although open to many objections, 

 is very useful, and is generally employed by modern authors. 



The divisions are as follow : — I. Pentamera, in which all the 

 tarsi are five-jointed ; 2. Hetcrojnera, in which the four anterior 

 tarsi are five-jointed, and the two posterior four-jointed ; 3. The 

 Tetremera, those which have four joints to all the legs ; 4. The 

 Trimera, which have never more than three joints to all the tarsi. 



It must be understood that this classification is very artificial, 

 for there are many beetles which are very closely allied so far as 

 their general structures are concerned, which have great differences 

 in the numbers of the joints of their legs ; and, on the contrary, 

 those whose joints are of the same number, are occasionally noticed 

 to be very different in their other characteristics ; so that the 

 number of the joints does not always coincide with the natural 

 affinities of the insects. This ready method must, therefore, give 

 way to one which groups the Coleoptera by considering the general 

 characters. 



The family of the Scarabceida; is, perhaps, the most interesting 

 as well as the most numerous of the Coleoptera, and its members 

 present remarkable distinctions in their habits, food, methods of 

 life, and in their general conformation. Nevertheless, although they 

 vary so very much amongst themselves, these beetles constitute a 

 very natural and very characteristic assemblage. They possess 

 antennae which are short and inserted into a cavity underneath the 

 lateral edges of the head, and which end in a club-shaped mass 

 made up of several leaflets. The antennae enable us to distinguish 

 most of the Scarabcsides at once. 



Dumeril, who was a good naturalist, called these Coleoptera the 

 Lamellicorjies, from the structure of their antennae ; but it should 

 be noticed that all of these organs are not composed of leaflets or 

 lamellae. Some are in the form of a cone reversed, or are nearly 

 globular towards their ends, the joints being box-like. The tarsi 



