TIIE COLEOPTERA. 2 67 
the other by attributing 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 Coleoptera into four great primary divisions, 
according to the particular number of the joints of the tarsi. 
Geoffry, 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: — 1. Pentamera , in which all the 
tarsi are five-jointed ; 2. Heteromera , in which the four anterior 
tarsi are five-jointed, and the two posterior four-jointed ; 3. The 
Tetrcniera, 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 Scarabceidce 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 Scarabceidce at once. 
Dumeril, who was a good naturalist, called these Coleoptera the 
Lamellicornes , 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 
