MFK-iriSTonv or a Mo.voj'iiLKiiUS. 133 



post ia of the first importance, in order that an endeavour may 

 be 0iade to prevent its spreading into Sal areas at present free 

 from it, and that species of like character, in the avbnt of tiieir 

 only too probable occurrence, may bo dealt with in the light of 

 acquired experience. 



Present observations show that the female is the chief 

 aggressor; but it must be borne in mind that it lias yet to bo 

 proved that there is not a second subcortical stage which is 

 likely to do much injury to the trees. The damage arising is 

 due to the heavy loss of sap the trees suffer owing to the 

 continual tapping for several months on end. In the cold 

 weather months from November to February this is perhaps not 

 serious, since the insect is then feeding upon the old leaves. 

 The sap is down and growth has probably ceased, and the 

 clogging of the stomata by the excreted fluid is perhaps the mo.-t 

 serious effect at this period. The injury really begins to become 

 acute when the coccid has got down to the twigs. The heavy 

 loss of sap resulting from its attacks at this stage cannot be 

 otherwise than most serious in months when the tree requires 

 all its vitality to enable the spring leaf-buds to develop perfectly 

 and. the flower-heads fully to mature. It is just at this period, 

 the most dangerous one for the tree, that the attack of the 

 Monoplilelus is culminating. Experiments have been commenced 

 with the object of discovering : 



(i.; The effect upon the devf-lopment of the spring crop of 

 leaves of a bad infestation by the coccids ; 



(ii.) The effect of the same upon the maturing and vitality of 

 the seeds. 



The attacks are more s^evere in dry years, since the scale is 

 then in greater abundance. 



The damage atributable to the insect may be summarized as 

 follows : — ■ 



(a; The clogging-up of the stomata and pores of the leaves 

 and twigs by the sugary secretion. This envelops leaves and 

 tv\igs, &c. with a sticky film which dries in the sun, giving them 

 the appearance of having been varnished. If the year is a wet 

 one the film is rapidly dissolved off by the rain, but in dry 

 seasons it remains for several months in situ, 



(I) Twigs and small branches dry up and die off under tlie 

 excessive tapping. This latter occurring in the spring has a 

 most serious effect upon the development of the spring crop of 



