14 



(c) Canes on which the insects have already been killed by fungus 

 possess only very small peep holes, as if the animal finding the insects 

 dead has gone elsewhere. 



(d) Where there is a " window " there are never any insects on 

 the exposed sxirface of the parent cane, but on lifting back the remainder 

 of the leaf sheath the insects are found on either side of the " window." 

 The animal, therefore, can only get at the insects where it has torn 

 away the leaf sheath. 



(e) Scratches are found on the surface of the cane such as might 

 be made by the teeth of an animal in removing the insects. 



There is very little doubt that the rat is responsible for these 

 windows as rats are abundant in the fields. Indeed it is difficult to 

 see what else it would be. On one inspection rats were seen high up 

 on the cane, and an examination of the cane showed that the rats 

 had just been disturbed whilst in the act of making the "windows." 

 The stalks of the canes were only found bitten through by rats where 

 they were uninfected or only very slightly infected, and it appears that 

 the rat has a very decided partiality for a diet of this particular insect. 



This can never constitute more than a subsidiary control as 

 it does not come into action until the infection is heavy, but it certainly 

 assists in preventing the attack from becoming overwhelming. 



(2) There are two distinct fungoid attacks or possibly they may 

 be two stages of the same fungus. 



The more prevalent by far is a green fungus. An insect attacked 

 by this appears at first rather more waxy than usual and short filaments 

 bearing sporangia arise from the body of the attacked insect. These 

 sporangia are at first white but rapidly turn yellow green and then 

 grass green. The insect is killed very quickly and becomes a hard 

 dark mass covered with the green fungoid growth. Insects of all 

 sizes were found attacked by this fungus irrespective of whether they 

 were isolated or in large colonies and all stages from one insect to 

 every insect in a colony being attacked were observed. In some cases 

 at least 50 per cent of the insects on a cane had been killed by this fungus. 



The other fungus is white and commences by an opaque white 

 film forming on the mother cane underneath the insect. In a colony 

 this white matter increases, filling up the interstices between the 

 individual members and then growing over them so that they become 

 completely enveloped and present a soapy opaque white mass. All 

 the insects have long since been killed and on breaking up the mass 

 it is found to be green within. This fungus was found to^ attack 

 colonies rather than individuals. 



It appears that the green fungus grows directly on the insect, 

 killing it, whilst the white fungus grows around it and death from 

 suffocation ensues. 



