206 INSECT ARCHITECTURE. 



roughly. The egg is, for the most part, placed upon the 

 mid-rib of the rose-leaf, but sometimes on one of the 

 larger nervures. When once it has got within the leaf, 

 it seems to pursue no certain direction, sometimes working 

 to the centre, sometimes to the circumference, sometimes 

 to the point, and sometimes to the base, and even, occa- 

 sionally, crossing or keeping parallel to its own previous 

 track. 



The most marvellous circumstance, however, is the 

 minuteness of its workmanship ; for though a rose-leaf is 

 thinner than this paper, the insect finds room to mine a 

 tunnel to live in, and plenty of food, without touching 

 the two external membranes. Let an}'- one try with the 

 nicest dissecting insti-uments to separate the two plates of 

 a rose-leaf, and he will find it impossible to proceed idr 

 without tearing one or other. The caterpillar goes still 

 further in minute nicety ; for it may be remarked, that 

 its track can only be seen on the upper, and not on the 

 under surface of the leaf, proving that it eats as it pro- 

 ceeds only half the thickness of the pulp, or that portion 

 of it which belongs to the upper membrane of the leaf. 



We have found this little miner on almost every sort of 

 rose-tree, both wild and cultivated, including the sweet- 

 briar, in which the leaf being very small, it requires nearly 

 the whole parenchyma to feed one catei-pillar. They seem, 

 however, to prefer the foreign monthly rose to any of our 

 native species, and there are few trees of this where the}^ 

 may not be discovered. 



Tunnels very analogous to the preceding may be found 

 upon the common bramble {Rabns fruticosus) ; and on the 

 holly, early in spring, one which is in form of an irregular 

 whitish blotch. But in the former case, the little miner 

 seems to proceed more regularly, always, when newly 

 hatched, making directly for the circumference, upon or 

 near which also the mother moth deposits her eggj and 

 winding along for half the extent of the leaf close upon 

 the edge, following, in some cases, the very indentations 

 formed by the terminating nervures. 



The bramble-leaf miner seems also to differ from that 



