
























COLEOPTERA. 503 
| him board and lodging. The Ptilodactyde, the Eucineti, and the 
Cebrios belong to the same family. The first two are exotics. 
The Elateride are rather large insects, often of hard texture, 
having the prosternum prolonged into a point (Figs. 549 and 
550), and the antennz indented saw-wise. They have the power 
of jumping when placed on their backs, and of alighting again 
on their legs. Hence their name of Elater (derived from the same 
| root as the word elastic). They produce, im leaping, one sharp 
rap, and often knock many raps when they are prevented from 
projecting themselves. This is the mechanism which permits the 

Fig. 550.—Jumping organ of the Elater, 
seen sideways. 









Fig. 549.—Jumping organ Fig. 551.—Larva of the Elater. 
of the Elater. 
skip-jack to execute these movements. It bends itself upwards 
by resting on the ground by its head and the extremity of 
the abdomen; and then it unbends itself suddenly, like a 
spring. The point at the end of the thorax penetrates into 
a hollow of the next ring; the back then strikes with force 
against the plane on which it rests, and the animal is projected 
into the air. It repeats this manceuvre till it finds itself on 
its belly, for its legs are too short to allow of its turning over. 
Its structure supplies it with the means and the strength of 
rebounding as many times as it falls on its back, and it can thus 
raise itself more than twelve times the length of its body. 
The larve of the Elaters (Fig. 551) are cylindrical, with scaly 
skin and very short legs. They live in rotten wood or in the 
roots of plants. According to M. Goureau, they pass five years 
in this state. 
The larve of the genus Agriotes occasion considerable damage 
