132 Mr. K. Kunhi Kannan on 



Pulvinaria psidii is known popularly as the " mealy 

 bug" * for the reason already mentioned, that it secretes 

 a large quantity of waxy substance which appears like 

 cotton and forms a sort of cushion beneath the abdomen 

 of the insect, lifting it up and bringing it at an angle to 

 the surface of the leaf. The eggs are laid in this mass. 

 Like green bug, it is quite at home on a variety of plants, 

 viz. Coffee, Tea, Cinchona, Citrus plants, Eugenia, Guava, 

 Myrtle, Ficus, Cardamom, Duranta, Garcinia, Antidesma, 

 Alpinia, and numerous other plants. 



Both these species have been studied in the Entomo- 

 logical Section of the Department of Agriculture in Mysore, 

 ever since Coccus viridis appeared as a pest in the State 

 in 1912, and this paper attempts to give some of the results 

 of the investigation and their explanation. 



When the pest first appeared, a number of planters 

 sent in specimens for identification. All these w T ere deter- 

 mined as Coccus viridis, as they answered in all respects 

 to the description of the species given by Green in his 

 book " The Coccidae of Ceylon." About a year afterwards, 

 when specimens happened to be microscopically examined 

 again, a remarkable change had appeared. The antennae, 

 which are seven-segmented in the species, showed a reduc- 

 tion to three by the coalescence of the five apical segments 

 into. one. Several hundreds of specimens from all parts 

 of the State were then examined, but none with seven- 

 segmented antennae were found. From one estate, 

 however, from which specimens were obtained immediately 

 on the outbreak of the pest there in 1913, a few bugs were 

 obtained which showed four or five segments in the an- 

 tennae (PI. VII, fig. 4, drawing i). Specimens from the 

 Pulneys, Shevroys, the Nilgiris, and Coorg have also been 

 examined, and all show a reduction to three segments, 

 though in some there are traces of additional segmentation. 

 There is little doubt, therefore, that in South India the 

 three-segmented condition of the antennae is practically 

 universal, though there is one important exception to 

 which reference will be made later. 



The reduction may make it appear probable that the 

 bugs originally identified by Dr. Coleman and myself were 

 not the same as the bug described by Green. Since, 



* Pulvinaria psidii may be locally known as "mealy bug" in 

 Southern India; bul that term is more usually applied to members 

 of the genus Pseudococcua and its allies. — E. E. G. 



