THE LINNEAN ORDER NEURCPTERA. 27 



The Stone-flies are at present very little understood, owing in 

 great part to the difficulty in studying them, as they shrink up unless 

 preserved in fluid. About a couple of dozen species are recorded 

 as occurring in this country. 



The EphemeridcB or May-flies are easily known from the shape 

 of the wings, their very short antennae, and also by the possession 

 of two or three long setse, which project from the anal segment; 

 the setae are often as long as or longer than the wings. Some of 

 the stone-flies have long setae, but these can be at once separated 

 from the May-flies by their long antennae, ample hind wings, &c. 

 About forty species of May-flies occur in this country. The 

 best method of preserving the stone- and May-flies is in fluid. 

 The Kev. A. E. Eaton, the best authority on the May-flies, says, 

 " It is sufficient for ordinary purposes to dip the freshly-killed 

 specimen into dilute spirits, and then transfer it to a tube or 

 homoeopathic globule bottle partly filled with water ; next, Price's 

 glycerine is added to the water, — one or two drops a day, — until 

 the bottle is gradually filled. A small drop of acetic acid may be 

 added finally, to prevent the growth of mould." 



The Odonata, or dragon-flies, are familiar to all who may ever 

 have hapjDened to take a walk during a warm summer day near a 

 weedy pond, where these insects may be seen hawking after 

 their food, viz., small insects, or carrying on a very important 

 duty, their amours. I know no more beautiful sight than that of 

 a few of the "Devil's darning-needles" (as they are familiarly 

 called in Scotland) making their exquisite curves while chasing 

 one another in some quiet glade near a picturesque pool. 

 About half-a-hundred species are known to occur in Britain, 

 of which many are adorned with the most brilliant metallic 

 colours, which do not fade ; unfortunately a few of the more 

 tender-bodied ones do fade, but then it is always possible to pick 

 out a few from a series that have retained most of their colour. 

 It must also be borne in mind that specific distinction depends 

 more on structure than on colour in the Neuroptera. 



The second suborder is the Neuroptera-Planipennia, or lace- 

 wing flies, which are no doubt the most lovely of all the British 

 Neuroptera, one or two of the dragon-flies excepted, many of the 

 species rivalling any of the LcpidojJtera in beauty of colour, 

 although the colours in the Planipennia are produced by different 

 means, namely, bv iridescence. Chsiracteristic insects of tiie 



