The resemblance of some of the members of the Homopterous 

 families Psyllidae and Aphidae to Aleyrodes is worthy of mention. 

 Many years ago, Signoret, who was a prominent French entomolo- 

 gist and an authority on the Coccidae and Aleyrodidae, classed with 

 the latter family the genus Spondyliaspis, which Maskell* states be- 

 longs without doubt to the family Psyllidae. Among the Aphidae, 

 some of the Pemphiginae bear a striking resemblance to the larva 

 and pupae of Aleyrodes. These cases at least illustrate how insects 

 like the Aleyrodidae and Coccidae could have arisen from primitive 

 Homopterous forms which had well developed legs in all larval 

 stages, and well developed legs and two pairs of wings in both sexes 

 of the adult. 



From our present knowledge it seems probable that the Aley- 

 rodidae and Coccidae are more closely related to one another than 

 either is to any other group, but further study of the least specialized 

 members of each family is necessary before any definite conclusions 

 can be drawn. 



Methods of Study. 



Aleyrodes, on account of their delicacy and small size, offer 

 some difficulties to a beginner. The immature stages are best 

 handled with a needle, aided by a good hand lens. The needle 

 should be inserted between the body of the insect and the leaf, pre- 

 ferably from the side. The insects can then be lifted and deposited 

 on a slide by rolling the needle, or if the larva is in the first instar 

 and crawling, it may be allowed to crawl off the needle point. In 

 the latter case the slide should then be placed in a strong cyanide 

 bottle for about five minutes. No cover glass need be used for ordi- 

 nary study with a one-fifth or even Zeiss F objective. To use an oil 

 immersion lens a thin cover glass should be placed over the insect, 

 resting on three or four, dots of thick balsam. In this paper the 

 descriptions and drawings of the immature stages are based princi 

 pally on fresh specimens mounted as above. 



* Transactions New Zealand Institute, vol. xxviii, p. 415. 



