176 STRANGE DWELLINGS. 



the outline, keeping to the edge, and not trenching at all on 

 the central portions. 



Insects belonging to three orders are known to make these 

 curious habitations.; namely, the Lepidoptera, the Coleoptera, 

 and the Diptera. Of these, the Lepidoptera are by far the most 

 numerous, and belong to that group which is called, on account 

 of their very minute dimensions, the Micro-Lepidoptera. These 

 are all little moths, so small that on the wing they can scarcely 

 be recognised as moths, and look more like little flies. They are 

 all very beautiful, and many of the species are truly magnificent 

 when seen through a microscope, their plumage glittering as if 

 made of burnished gold and silver. Indeed, one genus in which 

 these leaf-miners are comprised, is named Argyromiges, a title 

 based on a Greek word signifying silver. 



As for the beetle leaf-miners, they are to be found among 

 the weevils ; and it is a remarkable fact that one of these 

 insects belongs to the genus Cionus, which in their larval con- 

 dition are not only leaf-miners, but weavers of certain beautiful 

 pensile cocoons. 



Of the Diptera, the Celery Fly {Tephritis ojiopordinis) is a 

 good example. The larva of this really pretty fly, with its 

 green eyes and black and white spotted wings, feeds not only 

 on the celery but on the parsnip, and does great harm to both 

 plants. Gardeners often employ little boys to examine the 

 celery plants, and whenever they find a ' blister,' as they 

 technically call it, to crush the inclosed maggot between the 

 fingers. The colour of this larva is pale green, so that it is not 

 readily seen even when the blister is opened. If allowed to 

 have its own way, the larva remains in the leaf until it has 

 finished its eating, and then descends into the ground, where it 

 changes into the pupal state, and remains until the following 

 spring. In such a case, the leaves are often much damaged, 

 the blisters being yellowish white, and the leaf itself drooping 

 and half withered. 



Our last examples of pensile nests are taken from the Arach- 

 nida, being formed by several species of spiders. 



