VIII 



ALEURODIDAE 



59 1 



I. 



by carrying them to those plants. 1 We have nearly 200 species 

 of Aphidae in Britain, 2 and there may perhaps be 800 known 

 altogether. To what extent they may occur in the tropics is 

 undetermined. There are said to be no native species in Xew 

 Zealand. 



Fam. 8. Aleurodidae. Minute Insects, with four mealy 

 seven-jointed antennae, two-jointed feet, terminated by two 

 and a /// //v/ process. These minute Insects are at present a source 

 of considerable perplexity, owing to the curious nature of their 

 metamorphosis, and 

 the contradictory 

 accounts given of 

 them. In the earlier 

 stages they are 

 scale - like and qui- 

 escent, being fixed 

 to the under side of 

 a leaf. The French 

 authors Signoret and 

 Girard state that the 

 young are hatched 

 having visible ap- 

 pendages and seg- 

 mentation, but that 

 after they are 

 attached to the leaf 

 the organs gradu- 

 ally suffer atrophy. 

 Maskell states the 

 opposite, saying that 

 the organs in the 

 earliest stages are not usually recognisable, but become faintly 

 visible with the growth of the Insect. Heeger states that 

 the larva undergoes three ecdyses, and he gives the figures 

 we reproduce ; if he be correct it would appear that the 

 nymph undergoes a great development. l,'<auiimr, on account 

 apparently of their great metamorphosis, treated the 



C 



FIG. 287. Instars of Aleurodes immaculata. Europe. 

 (After Heeger.) A, Nymph, from above ; B, nymph, 

 under surface ; C, imago. 



1 J. Xi'n- r<'/7- Knl. Soc. i. 189.3, p. 120. Sec also as to knowledge on thr pan 

 of ant-. Forbes, /v'/y///,. ,iih /,'<//. //(>/.% //////. ,X IS'.M, pp. M, rtr. 

 - Monograph l>y I'.iu-kton, /.'".'/ .S'<-/ ( 7//, 4 vols. 1879-1883. 



