TIIK STONE-FLY. 



493 



two years in their preliminary stages of existence. In the larval and pupal states, they 

 are inhabitants of the water, and are fond of hiding themselves under stones, or burrow- 

 ing into the muddy banks. Under the latter circumstance they make a very curious 

 lunnel, something like a double-barrel gun. It is said that the larva feeds upon mud, 

 ;<ml, as a proof of this assertion, it may be mentioned that Swammerdam always found 

 mud within those specimens which he dissected. I can personally vouch for the ac- 

 curacy of his remarks, but would not like to assert that, although mud was always 

 found in the stomach and intestines of those larvae which I have dissected, it might 

 not have been swallowed with the food rather than composed it. 



Nemoptera Coa. 



ANT-LION. Myrtneleon translates. 

 MAY-FLY. Ephemera vulgata. 



The May-fly is peculiarly notable for a stage of development which seems to be 

 quite unique among insects. When it has passed through its larval and pupal state, 

 it leaves the water, creeps out of its pupa case, and takes to its wings. After a period, 

 varying from one to twenty hours, it flies to some object, such as the trunk of a tree 

 or the stems of water-plants, and casts off a thin membranous pellicle, which has en- 

 veloped the body and wings, the dry pellicle remaining in the same spot, and looking 

 at first like a dead insect. After this operation, the wings become brighter, and the 

 three filaments of the tail increase to twice their length. Some authors call the state be- 

 tween the leaving the water and the casting the pellicle the " pseudimago " state. 



Some of these insects are well known to fishermen under the names of green and 

 gray drake, the former being the pseudimago, and latter the perfect form of the insect, 

 which is represented in the illustration. Sometimes these insects occur in countless 

 myriads, looking like a heavy fall of snow as they are blown by the breeze, and having 

 on some occasions been so plentiful, that they have been gathered into heaps and cart- 

 ed off to the fields for manure. 



The Perlidae, known to anglers by the name of STONE-FLIES, belong to the Neurop- 

 tera. - Several species of the same family are popularly called Yellow Sally and Wil- 

 low-fly. 



