= 2 == 
quite possible that they may act as distributors of bacterial and 
vegetal disease germs. 
On several occasions countless numbers of Collembola have been 
sent me from sewage works. What economic importance they have, 
there has not in any way been worked out. The enormous masses 
of them that sometimes occur in sewage farms is remarkable. 
Direct injury seems to have been traced to the following species :' 
List of injurious species. 
* Lipura armata TULLBERG. 
Lipura ambulans LINN AUS. 
Lipura burmeisteri LUBBOCK. 
* Lipura fimetaria LINN AUS. 
Achorutes armatus NICOLET. 
Achorutes manubrialis TULLBERG. 
Achorutes longispinus TULLBERG. 
Achorutes rufescens NICOLET. 
Achorutes purpurescens LUBBOCK. 
Anurida granaria NICOLET. 
Isotoma palustris MULLER. 
Isotoma tenella REUTER. 
* Orchesella cincta LINNA US. 
Entomobrya nivalis TULLBERG. 
Entomobrya multifasciata TULLBERG. 
Lepidocyrtus sp.? 
Sminthurus fuscus LINN.EUS. 
Sminthurus luteus LUBBOCK. 
Sminthurus niger LUBBOCK. 
Sminthurus pruinosus TULLBERG. 
Sminthurus hortensis. 
Templetonia nitida TEMPLETON. 
Degeeria annulata FABRICIUS. 
* 
The species personally observed are marked with an asterisk. 
LUBBOCK in 1872 said : « Some species of Sminthurus live on the 
leaves of plants » (1). 

(1) LugBocx, Mon. Collembola and Thysanura, Ray Soc. 1872. 
