LEAF-MINERS. 133 
well as several species of the larger genus Tephritis, 
some species of which live in the parts of fructification 
of several flowers, the common dandelion being infested 
by them. 
We may now describe, at fuller length than has hitherto 
been done, another group of insects, which live between the 
membranes of leaves, and which belong to different orders. 
LEAF-MINERS AND ROLLERS. 
If the reader will carefully examine the leaves of any 
rose-tree which grows in the open air, he will certainly 
remark that many of them are notable for certain curious 
markings, which look something like the rivers in a 
map, and which traverse the leaf in various ways. They 
all, however, agree in one point, namely, their gradual and 
