1897 



MICUOSCOPICAL JOURNAL. 



24 *J 



or the alkaline antiseptic tablet ol Dr. Carl Seller, one 

 dissolved in a teacup, half full of warm water. — Medical 

 Fortnightly. 



On Reariag Dragonflies. 



Hv .TA\[E>1 C vi.-iMinA>r, 



Field work in Entomology is full of delightful oppor- 

 tunities, and none is more inviting, none more sure to 

 yield discoveries of scientific value, than work upon the 

 life-histories of Dragonflies. 



The nymphs which are aquatic, 

 have an interesting distribution in 

 depth. Those of Agrionidae and 

 of most xleschinidae cling to the 

 lloating or submerged vegetation-. 

 These at least every aquatic collec- 

 tor has seen. Those of Libel lulidae 

 sprawl ni)on the bottom amid fal- 

 len trash. Those of Gomphinae 

 burrow shallowly along beneath the 

 film of sediment that lies on the 

 bottom, with the end of the abdo- 

 men turned up for respiration. 



It is very easy to collect them. A garden rake with 

 which to draw ashore the stuff to which they cling and a 

 pail of water in which to carry them home is all the 

 ajiparatus desirable in spring. Later when a new- 

 growth of weeds is rooted fast to the bottom, the rake 

 will have to be exchanged for a water-Jiet. Withdrawn 

 from the water, the nym[)lis render themselves evident by 

 tlieii' active efforts to get back, and need only to be picked 

 U[). The number of species one will find will generally 

 dci)end on the variety of aquatic situations from which 

 he colle'ets. The places to yiebl the^ best collecting are 



