on small-leafed plants, such as Calluna and Genista, cannot hide 

 themselves on the undersides of leaves like C. lineolea, C. viininete/la, 

 and others. Therefore they make themselves inconspicuous by so 

 constructing their cases that these shelters have the appearance of 

 being actually portions of the food-plant itself. When the case is 

 formed of such small leaflets as those of Callima or Cytisus, it 

 usually follows the principle of the beads on the string, but the hole 

 through which the string passes is occupied by the larva itself. I 

 have watched C. saturatella on a broom-leaf enlarging its case. The 

 process is as follows : the larva mounts to the apex of the leaf and 

 commences to mine a little on one side of the midrib. It mines out 

 sufficient parenchyma to clear the tip of the leaf, which it then splits 

 down the centre, wedging its case into the slit thus formed. The 

 case, with half the leaf sticking out on either side, is then fastened by 

 silk firmly into the split leaf, the rest of which is then mined out, and 

 lastly, the Whole cut off at the base. The basal half of the leaf now 

 forms the additional habitable portion of the case, while the project- 

 ing tip of the added leaf on one side and the split off portion on the 

 other, form the ornaments of the case. In drawing the added leaf to 

 shape the larva causes it to wrinkle a great deal in that part which 

 forms the tube or prolongation of the case. 



When, in early summer, the hawthorn leaves have grown sufficiently 

 large and the cuticles have become firm enough, we may find the 

 larva of C. hemerobiella spinning its curiously curved first case to the 

 base of a hawthorn leaf. When the case is firmly attached the larva 

 commences mining out — that is, eating out the parenchyma in a 

 straight line close to the edge of the leaf for a distance of about twice 

 the length and double the width of its own body. To do this it must, 

 of course, come quite outside its old case. When the mine is com- 

 pletely cleared of the parenchyma the larva cuts a slit in both 

 cuticles by gnawing along the inner margin of the mined space, from 

 the base, where the old case is attached, to the apex. It then spins 

 the two severed cuticles firmly together. The new case is now a 

 sheath composed of two walls, and is still attached to the leaf at base 

 and apex. The larva now mounts to the apex and severs one and 

 then the other cuticle from the leaf, but does not unite the lately 

 severed portions. It then returns to the base and treats that in the 

 same manner, clinging to the leaf with its thoracic legs as it finally 

 cuts the case clear of the leaf. It now crawls off in its new case, 

 leaving the old one attached to the leaf as though it were still 

 inhabited. After a day or two it completes the new case by forming 

 three valves at the apical aperture and by lining the case thickly with 

 silk. This process is adopted by the C. fusee ditiel la group and also 

 by the C. limosipenella group, except that the latter does not after- 

 wards close the apical aperture by three flaps. 



These, as far as I know, are the four chief methods adopted by the 

 Coleophonds in enlarging their dwellings. I must, however, mention 

 that the methods of case enlargement, though differing so greatly, do 



