414 INSECTS. 



materials may be rendered nauseous to them, and thus escape their 

 ravage, by having intermixed with them fragments of Russia lea- 

 ther, or other skins, that emit and retain a strong animal odour ; 

 and it is probably on this account, though the odour is far less 

 powerful, that this insect never commits its depredations on wool 

 while on the back of the sheep. 



8. P. pentadactyla. Body and wings snowy ; upper part bifid, 

 lower ones three-parted. A very beautiful European species, a 

 native of our own country, and of other parts of Europe; size 

 minute; the wing divided apparently into plumes, the upper by a 

 delicate midrif consisting of two, the lower of three, with innu- 

 merable lateral fibres. The larve is sixteen-footed, hairy, green, 

 with black dots, and a white dorsal line ; pupe hairy. green, dot- 

 ted with black. This insect belongs to the division pterophorus, 

 which constitutes a part of the alucita of Gmelin. 



9. P. hexadactyla. Wings cleft, cinereous, spotted with brown, 

 all of the six-parted. This also belongs to the division ptero- 

 phorus: it inhabits England, and Europe generally, and is found 

 on the loriscera xylosteum, or honeysuckle; and is likewise a 

 most elegant and beautiful insect. It often appears before our 

 windows, and flies in, when they are open, in a still and warm 

 evening in September. 



SECTION X. 



May. Fly* 



Ephemera vulgata. Linn. 



The ephemera genus exhibits a wonderful difference between 

 the same animal in its larva state, and that of its ultimate or per- 

 fect state ; the larva being altogether aquatic, the complete insect 

 aerial. It also affords an example of what may be termed a flying 

 pupa; since, in some species at least, the insect is no sooner 

 evolved from the larva than it flutters to the nearest convenient 

 spot, and again shifts its pellicle*, the wings themselves having 

 cast their exterior membrane. The ephemerae are extremely 



* This operation is so quick that it may be rather called springing from the 

 chrysalis than gradually emerging. 



