1911 ENTOMOLOGICAL SOCIETY. 70 



many of them to be deposited in more or less nearly complete circles. The female 

 lias been observed by different persons to accomplish this arrangement of them by 

 inserting her beak into the leaf and rotating around this as on a pivot. The eggs 

 hatch in about ten days, and the young larva? move about for a short time and then 

 insert their mouth parts into the tissues of the leaf and assume their scale-like form. 

 ^V^^en fully grovrn, which is in about two weeks, the larvae are less than a milli- 

 metre in length. After about two weeks longer in the pupal stage the adults 

 emerge. It is difficult to say how long they may live in the mature form. 



It is only a small family consisting of two genera and about 150 species. Like 

 many of the other families of insects of small size it has been much neglected. 



The two species attacking the Maple and Wild Ginger have a wide distribu- 

 tion in Ontario, especially in the Western portion of the Province. Aleyrodicus 

 asarumis have. been found almost everywhere that the Wild Ginger grows. It is 

 sometimes found on the White Baneberry at Guelph, but it seems to have a decided 

 preference for the Wild Ginger. It confines its attacks to the lower side of the 

 leaves and is usually so numerous as to almost cover this side of the leaf. Large 

 quantities of honey dew are given off by this species and the honey dew fungus nearly 

 always accompanies the insect. The life-history in Canada has not yet been 

 fully determined, but sufficient is known to prove there are at least two broods 

 during the season. It passes the winter in the mature form, but the writer has 

 not yet been able to find the hibernating quarters. Shortly after the Wild Ginger 

 leaves have expanded in the spring the White Fly may be found in the egg stage 

 on the leaf. In the course of a few weeks the affected leaves turn yellow and 

 myriads of the creatures may be seen at work. No insect parasites have been 

 observed at work on this species and from this we may infer that it has been some- 

 what recently introduced. 



Aleyrodes forbesii has been found as far east as Toronto, as far north as 

 Gravenhurst, and as far south as London, Ontario, and the indications are that it 

 is almost as widely distributed in Western Ontario as the maple itself. It is 

 the largest of the three species under discussion. The adults are rarely seen and 

 the large, box-like larvae are sparingly scattered over the under surface of the leaf. 

 The larv£e are pale green or whitish, somewhat the same color as their surround- 

 ings or environment and it is probably due to these two things that this species 

 has not been reported more often. The work of insect parasites has been observed 

 on several occasions in connection with this species and this probably accounts for 

 the comparatively small amount of injury done to the host. The ravages are much 

 less some seasons than others. 



It is interesting to note that the above two species are both found in the State 

 of Illinois. 



Aleyrodes vaporariorum is of ver}^ great concern to people engaged in green- 

 house work. From enquiry made to florists in all parts of Ontario it would appear 

 that not a single section is free from the pest. As it cannot, so far as is known, 

 winter in any stage out-of-doors, at least in its northern part of its range, it is 

 recognized principally as a greenhouse pest, but it is sometimes very common and 

 destructive to gardens and small fruits, especially in the vicinity where it is 

 carried over the winter in greenhouses. It appears to be very partial to members 

 of the family of plants known as the Solanacese, i.e., tomato, tobacco, etc. Several 

 reports have* been received from gardeners in different parts of the Province where 

 crops had been mined by this pest. It is sometimes very abundant on the straw- 

 berry and currant plants. In the fall when the temperature lowers they seek 



