G A R I) ]: X P K S T 8 1 X X E \V Z K A L A X 13 



Mealy bugs are controlled to a great extent by natural onemies, 

 among which are the Tasmanian lace wing (Mlcromu* las mania?) and 

 the Cryptola^mus ladybird (GryptoUemus montrouzicii), but the 

 influence of these is insufficient for commercial purpose-. Attempts are 

 now being made at the Cawthron Institute, Nelson, tc establish other 

 parasites recently imported from California. 



Control under glass is effective by means of fumigation, but in the 

 open is a more difficult matter, though red oil and lime-sulphur give 

 some satisfactory results, together with the pra ' rice of removing rough 

 bark on trees where the insects hibernate. In Xew Zealand are several 

 species of. mealy bugs, of which the following are of interest to the 

 horticulturist : 



LOXG-TAILED MEALY Bra ( Pseudoc0ccnx a 'Ion >!>ii m ) . This species 

 is readily recognised by the long tail-like appendages of the female. It 

 is widely distributed and commonly met with under glass, where it 

 infests almost any plant; in the warmer and moister districts of the 

 Dominion it occurs out of doors. Its list of host plants is a lengthy one, 

 and includes grape vine, passion vine, wistaria, fig, oleander, Phorniium r 

 cineraria, begonia, apple, plum, palms, ferns, etc. Considerable injury 

 may be caused by the insect when it occurs in dense masses on the under 

 side of foliage and upon young, succulent growth. 



Xo eggs are produced by this insect, the young being born alive ; 

 the production of young lasts for a period of from two to three weeks 

 at the rate of about twelve each day; the time taken to reach maturity 

 varies considerably, according to climatic conditions, the range being 

 from one to three months. There are comparatively few generations 

 each year out of doors, but under glass there may be several. 



CITROPHILUS MEALY BUG (Pseudoco:cus galiani). - - In Xew 

 Zealand this -species is met with on grape vines and begonia in glass- 

 houses, where it becomes epidemic if left uncontrolled ; out of doors it 

 infests apple and potato, and no doubt other plants are attacked. It is 

 characterised by the mealy covering being coarse and distributed 

 unevenly over the body, while the marginal fringe is short, the processes 

 being comparatively thick, particularly the tail-like ones, which are much 

 shorter than the body, though conspicuous. 



Egg-laying covers a period of about two weeks, from 394 to 679 eggs 

 being deposited by each female ; development to the adult is completed 

 in about six weeks, though this will vary according to the conditions. 

 In California four generations in the year have been noted. 



APPLE MEALY BUGS (Pseudococcus maritimus and P. comstocki). 

 Both these species occur upon apple, pear and potato in Xew Zealand, the 

 former species originating in America, and the latter in Japan; the 

 injury to the host itself is not severe, but the presence of these insects 

 on the fruit is responsible for apples and pears being rejected for export. 



Both species are very similar in appearance, and are of the short- 

 tailed type; they differ from the citrophilus mealy bug in having the 

 mealy covering evenly distributed over the body, while the marginal 

 fringe is delicate and thread-like. The eggs hatch in from one to three 

 weeks, and the larvae migrate freely, the insects reaching maturity one 

 or two months later, according to climatic conditions. In the open the 



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