G47 



lecanii, is the most important enemy of this scale, and during the 

 west monsoon enormous numbers are destroyed by it. The insect 

 enemies of C. viridis include Encyrlus bogoriensis, Zinmi., which is 

 said to infest about 15 per cent, of the fuU-grovvn scales and possibly 

 a good percentage of the smaller ones, and it should not be despised as 

 an enemy, though its development is too slow to make it effective against 

 a serious outbreak ; the larvae of a species of Eublemma ; the larvae 

 of Ephestia cautella, according to Zehntner ; the Coccinellids, Orcus 

 janthinus, Muls., which destroys large jmmbers, and Chilocorus melan- 

 ovhthahnus, Muls., which is less effective. According to Green, the 

 Chalcids, Coccophagus orientalis, How., Encyrtus JIavus, How., and 

 Ceraptocenis ceylonensis, How., de.'^troy this scale in Ceylon, and Ruther- 

 ford has added a moth, Cryplohlabesproleucella, to the list ; Epilachna 

 similis plays the same role in Africa [see this Revieiv, i, Ser. A, p. 247].* 

 With regard to Plagiolepis longipes, the ant which is accused of 

 protecting the scales and of being useful in spreading Cephalo- 

 sporium, the author considers that it is harmless to coffee because 

 it does not assist the spread of this scale, which it does not 

 cultivate. It materially assists the spread of Cephalosporimn 

 and checks the development of the sooty fungus by consuming 

 the secretion of the scale. OecophyUa smaragdina is to be regarded 

 as a pest, in that it to some extent protects the scales. The 

 planters' remedy against the scale is to limewash the plants, which is 

 considered a good method if thoroughly well done, but conditions 

 make this difficult. Cyanide fumigation has been tried successfully, 

 but is too costly and lengthy a process. The maintenance of vigorous 

 growth in the plant is a most important means of protection. Meijer 

 found that manuring with a mixture of kainit and lime freed the 

 plants from scale. Petroleum soap emulsion must not be used, as the 

 coffee leaf is very sensitive to petroleum and serious scorching occurs ; 

 a 4 per cent, solution of soft soap in water is the most practical 

 scalecide. Smoke from heaps of twigs and dead leaves arranged in 

 lines was systematically tried for a whole month on one plantation of 

 17 acres, but the results have not yet been reported ; this method 

 has proved useful against Helopeltis, but there is some doubt as to 

 its efficiency against scale-insects. 



The second section of this work deals with Pseudococcus bicaiidaius, 

 sp. n. (the two-tailed white scale). Both sexes are described. The 

 distinctions between the larvae of P. bicaudatus, which is believed to 

 be a native pest, and C. viridis, are given. The female lays three or 

 four hundred eggs, which hatch in a few hours. The rate of movement 

 of the young larvae is about 3 inches per minute and they retain well 

 developed feet throughout life. The larva is full grown in about 

 6 weeks and in one case, 39 days after placing a full grown insect on a 

 tree, a third generation appeared ; this very rapid multiplication 

 explains the statements of planters that this scale appears suddenly. 

 P. bicaudatus occurs from 200 to 3,1.00 feet above sea-level and dry 

 weather suits it best; ; it thus reaches its maximum at the end of the 

 east monsoon. Heavy rains wash the insects from the trees on to 



* Seeing- that E. sitnilis, like all its congeners, is undoubtedly a plant- 

 feeder and is occasionally an important pest of cereals, Morstatt's 

 statement, here quoted, appears to need confirmation. — Ed. 



