26 THE CA.NADIAN ENTOMOLOGIST. 



spines of the first instar and the first pair of dorsal spines of the pupa 

 were, unfortunately, omitted, see plate 2.) 



I have never seen an Alcyrodes vaporariorutn on a strawberry plant 

 out of doors. Specimens of Aleyrodes from Kentucky were recently 

 received through Prof. C. H. Fernald from Prof. Garman on strawberry 

 leave?, and were found to be identical with the common strawberry 

 Aleyrodes of this locality. Experiments thus far have shown that 

 Aleyrodes vaporariorum when transferred in the first instar to a straw- 

 berry plant will live and develop all the characters of those which feed 

 on the more natural food-plants of the species, while at three different 

 times crawling larvae of the strawberry Aleyrodes were transferred to fresh 

 leaves of a growing tomato plant, and all died within a few days, 

 apparently without taking any food. That the Aleyrodes vaporariorum 

 does not naturally feed on the strawberry is shown by the fact that a 

 strawberry plant in a pot remained for over six months in a greenhouse 

 thickly infested with that species and less than half a dozen Aleyrodes 

 matured on its leaves, upon which even the imagoes were very rarely ob- 

 served resting. It does not seem strange that where the natural food-plants 

 were so thickly infested an egg should occasionally be deposited on other 

 plants. 



Iricidentally it might be mentioned that /// this locality the straw- 

 berry Aleyrodes in all its stages, including the egg, averages a little larger 

 in size than the greenhouse Aleyrodes (Aleyrodes vaporariorum). 



Egg (Plate 2, Fig. 1). 



The egg is irregularly oval, with one side more or less flattened ; 

 attached to the leaf by a short stalk, situated on the basal or more 

 broadly-rounded end, usually a little to one side of the centre, toward the 

 more rounded side. When freshly laid, the egg is pale green in colour, 

 with a rounded orange-yellow body within, in a few days changing to a 

 metallic bronze colour. The surface of the egg is unmarked. The length, 

 exclusive of the stalk, is from .23 to .24 mm.j greatest width, from .08 to 

 .095 mm. The stalk is from yk \.o y^ the length of the egg. 



The length of the egg stage depends upon the weather conditions. 

 Those laid in late fall do not hatch until the following spring, while in the 

 warm summer weather they Inilch in about eight or ten days. 



First Instar (Fig. 2). 



In the first instar the general form is oval, the anterior end being the 

 more broadly rounded, the sides of the thoracic region are approximately 



