213 
MINING INSECT ON THE ROSE TREE. 
BEING AN EXTRACT FROM THE OBSERVATIONS OF E. W. LEWIS, ESQ. 
As inserted in the Entomological Magazine, Vol. I. p. 424= 
It has, no doubt, been observed by many, that in autumn the leaves of the 
rose tree on then- upper surfaces are very often marked in various directions with 
broad brown lines, having- a narrow blaclr one running- down the middle. This 
curious appearance is caused by the small caterpillar of a minute moth {Wlicrosetia 
rvficapitella) which feeds inside of the leaf. 
When full grown, the caterpillar is nearly two lines long-, of a yellow orange 
colour, with a brown mark down the back, the head very flat and sharp, and lig-ht 
chocolate. 
The brown mark on the leaf is caused by the epidey^mis drying, from the insect 
having- eaten the parenchyma, or substance of the leaf beneath ; the black one by its 
egesta, which, during- its young state, entirely stop up the mine. 
When full grown, which is about the 24th of October, it eats out of the leaf, 
and crawls down the branches and stem, until it has found a convenient place to fix 
its cocoon. This is the only time when it finds it necessary to make use of its legs, 
which seldoms exceeds an hour, sometimes less. 
After having found a suitable place, which is generally about the sy>ines and 
offsets of the branches, it begins to form the cocoon, by stretching out its body and 
attaching a thread to the branch ; it then crosses its body to the other side and 
there fastens it. By proceeding thus on all sides, keeping the hinder part of the 
body fixed, it forms the upper part of the cocoon, or that exposed to the weather, 
which is convex^ and generally circular ; the under part is oblong, shaped to hold 
the pupa, and much smaller than the upper, which projects considerably beyond it 
on all sides. At one end the threads are not interwoven, and leave a space through 
which the pupa can force a passage. 
This remarkable cocoon is very flat, and at first of a pure white, which is changed 
by the first shower of rain to light orange ; it afterwards becomes of a deep brown, 
so nearly resembling the bark of the rose tree as only to be distinguished by a 
practised eye. This change takes place very rapidly. When kept dry, the cocoon 
remains perfectly white, and produces the moth at the usual time, as well as those 
which have been saturated with water. 
The pupa is light brown, of an oval shape, about a line long, and half that in 
breadth, and the perfect moth appears about the 12th of May. 
The moth is the red-headed pigmy {JTinea rujicapitella^ of Haworth). The 
upper wungs are gold coloured, with the apex purple, the head ferruginous, the 
expansion of the wings 2| lines. 
