COLEOPTERA. 
r 57 
nearly always brightly metallic or otherwise conspicuous. Some of the species 
are very gregarious in their habits. Lina tremulce is often found in large numbers 
in all its stages on the leaves of aspen; the larvae are 
somewhat like those of lady-birds, and have the habit 
of exuding a strong-smelling yellow liquid from the 
mouth and other parts of the body. The Colorado 
potato - beetle (Leptinotarsa decemlineata ) is very 
destructive to the potato crops in North America. The 
Oalerucinoe are poorly represented in Great Britain, 
while of the flea-beetles ( Halticince ) we have a large 
number of species, of which the best known are the 
turnip-flea (Phyllotreta nemorum), and other little 
jumping beetles which attack cruciferous plants. The 
larvae of the Halticince usually mine in the tissues of 
the leaf underneath the epidermis; in this respect 
differing from the larvae of most of the other 
Chrysomelidce. The Cryptostomata are distinguished 
by having the front of the head inclined backwards 
so that the mouth is almost completely hidden. Two 
subfamilies are included in this section. The Hispinai 
are remarkable for the sharp projecting spines with 
which many of the species are armed, while the 
Cassidince have the characteristic form to which they 
owe their name of tortoise-beetles. In Great Britain, 
the tortoise-beetles are represented by half a dozen or more species of the genus 
Cassida, one of which (C. nebulosa ) in its different stages is illustrated in our figure. 
COLORADO POTATO-BEETLE IN ALL 
its stages (nat. size). 
LIFE-HISTORY OF THE TORTOISE-BEETLES ( CdSSulince). 
1, Cassida nebulosa ; 2, The beetle (enlarged); 3, The larva (nat. size); 4, The pupa, and 5, the larva (both 
enlarged); 6, Desmonota variolosa, with leg and portion of elytron enlarged. 
A Brazilian species ( Desmonota variolosa), remarkable for its deeply sculptured 
elytra and bright golden-green colour, is also shown in the same figure. 
