[ 73 ] 



^be paraeitic fungi of Jneecte^ 



By George Norman, M.R.C.S., F.R.M.S. 



Plates 6, 7, and 8. 



HE Fungi of Insects may be roughly divided into 

 two classes, according to their method of obtaining 

 nutriment : — 



I. — Those which obtain their nutriment entirely 

 from living hosts, whether animal or vegetable, and 

 ll_^'^_5^ which are called Parasites. 



°^V*^^\J^ 2. — Those which live entirely on dead organic 



^IkL^ matter, whether animal or vegetable, and which are 



termed Saprophytes. 

 Between these two extremes, however, there are numerous 

 gradations — such, for instance, as where 2^ parasite growls upon and 

 kills its host, and then continues to vegetate as a saprophyte upon 

 the dead tissues. 



The Parasitic Fungi affecting plants are exceedingly numerous, 

 but those affecting insects are comparatively few, though important 

 in some cases, at least from an economic point of view. 



The Fungi parasitic on insects, although formerly assigned to 

 one or other of the older and well-known groups, have of late 

 years, as their life -history has become better known, been placed 

 in groups by themselves, adjacent to, but not belonging to the old 

 divisions. 



Thus the Entomophthoreae, formerly included in the Torulacei, 

 are now placed in a separate group, adjacent to the IMucorini ; 

 whilst another group, the Laboulbeniese, formerly included in the 

 Ascomycetes, are now tentatively placed along-side them. There 

 is, however, one important exception, in the case of Cordyceps or 

 Torrubia, which, at any rate for the present, retains its place 

 amongst the Ascomycetes. 



Laboulbenie^. 



This group, more nearly allied to the Ascomycetes than to any 

 other family, presents numerous peculiarities quite entitling it to 



Journal of Microscopy and Natural Science. 



New Series. Vol. III. 1S90. g 



