26 PB6TS OF COFFEE 



convex. Several other curious forms are produced by in- 

 dividual methods of fixation. In some, the anterior end 

 appears as a distinct lobe projecting from the body ; in 

 others, curious projections may appear on tlie anal lobes. 



Feeding. 



Convulsive movements may be seen through the 

 chitin, while the bug is feeding. These are probably due 

 to the pumping action of the alimentary canal. Feed- 

 ing apparently continues until the death of the insect, 

 but no definite statements can be made in this regard. 

 Mealy bugs, previous to oviposition, seek such situations as 

 folds of dry leaves, the dry scales of the bark, etc., where 

 nutriment is out of the question. Specimens of green 

 bugs were found alive even after a burial under ground of 

 about twenty days. Nevertheless it appears probable that 

 feeding continues at least throughout the period of repro- 

 duction. The interval between the end of reproduction 

 and the death of the insect varies from one day to as 

 many as four days, the commencement of discolouration 

 of the bug being taken as evidence of death. 



The course taken by the proboscis in the tissues 

 of the leaf and the tissues from which nourishment is 

 chiefly drawn have formed the subject of study by 

 Keuchenius in Java, and as the positions occupied by our 

 form on the leaves and twigs is much the same, it is pro- 

 bable that this represents the method of feeding here 

 also. The following account is abridged from his descrip- 

 tion:—^ 



Lecanium viride (Coccus viridis) usually, in penetra- 

 ting the leaf, pierces the cuticle of the epidermis in the 

 middle of an epidermal cell. One of the results of pene- 

 tration is commonly a certain amount of plasmolysis in 

 the cells penetrated as well as in the neighbouring cells 

 but the original turgor is later on restored even in the 

 cells which have been pierced. The cells penetrated 

 show no signs of death and the cell walls do not turn 

 brown. The saliva which is emitted from the proboscis 

 during the penetration first appears as irregular masses 

 and only gradually takes on the form of a regular approxi- 

 mately uniform layer which later on hardens into a 



* Keuchenius, Loc. cit., p. 22. 



