INSECTS, MITES, ETC. 



263 



The commonest kind is known as Podura terrestris. It 

 varies in length from l-30th to I'm., is of a whitish colour, 

 and more or less hairy. When disturbed, it jumps or 

 runs away with alacrity. This species frequents damp and 

 sour soils mainly. Other kinds of S^^ringtails which are 

 equally harmful are: Achorutes purparescens, a brownish 

 insect of similar size to the preceding one ; and Lipura 

 ambulans, a milky-white kind. The}^ are easily recog- 

 nised by their habit of jumping or springing when dis- 

 turbed. 



[Photo: J. G. Blakey. 

 GHOST oil SNOW FLY iALEYl?ODES PROLETELLA). 

 The flies are magnified eight diaiiietere. Below are the waxen nymph casr.-. 

 containing the pupae. 



Eemedies. — Immersing the pots and roots in lime water, 

 as advised for worms ; watering the soil with a solution of 

 nitrate of soda at the rate of an ounce iper gallon, or with 

 a weak solution of permanganate of potash and water, will 

 destroy these creatures. 



Thrips. — There are "few insects more destructive than 

 these. The one which attacks the chrysanthemum and 

 other greenhouse plants is Heliothrip hsemorrhoidalis, 



