1912 ENTOMOLOGICAL SOCIETY. 65 



and begin to deposit their eggs. In the spring the eggs hatch in ten to fifteen 

 days; in the summer they will hatch from four to seven days after deposition. 

 The larvae are similar in general form and appearance to the adult except in the 

 possession of wings. They become full-grown in the spring in about two weeks 

 but in the hot days of summer tlie larval stage may be completed in four days. 

 The whole life cycle occupies from 12 to 30 days. The first winged adults usually 

 appear in May or June. An interesting point in connection with this species is 

 that it is parthenogenetic, that is^, the eggs will produce young without fertilization ; 

 Hinds has examined thousands of specimens of the species and has been unable to 

 discover the male. The ability of the female to deposit eggs which will develop 

 into young without the necessity df fertilization by the male increases the repro- 

 ductive power of the species enormously and we have in this insect a similar 

 phenomenon to that with which you are already acquainted in the case of the 

 Aphides, whose extraordinary fecundity is due, in a large part, to the partheno- 

 genetic character of the female. 



Feeding as this species does on wild grasses of various species, which flourish 

 in abundance everywhere, it will be readily understood that its control will be a 

 matter of considerable difficulty, as the Thrips migrate from one species of a plant 

 to another. The only method of control which will ever give any appreciable re- 

 sults on a large scale are methods of cultivation and farm practice. The dfestruc- 

 tion of weeds, especially those belonging to the family Graminese, is essential. The 

 Thrips appear to hibernate in places where they have been feeding, such as the 

 stems of grain which have died down, in crevices of the ground or under rubbish, 

 and the best method of attacking the insect in the hibernating stage is by burning 

 over the grass or stubble in the fall or the deep ploughing of the soil. These two 

 methods may be employed conjointly. . Korolikoff, who has been studying the differ- 

 ent species of Thrips injurious to cereals and grasses in Eussia, near Moscow, 

 recommends the sowing of strips of such crops as rye or oats round the field under 

 cultivation. These " bait " crops, as they might be termed, are sown about a 

 fortnight before the time of the sowing of the winter cereals in order that they 

 will be the first to attract the Thrips and afford them shelter while the crops are 

 growing. They are afterwards cut and their removal results in the removal of a 

 large proportion of the Thrips. 



As I remarked, however, at the outset, this investigation has only just begun 

 and my statements are only in the nature of a report on progress in the hope of 

 enlisting the assistance of any of the members, should an opportunity occur lo 

 them of supplying us with information which might be useful. 



THE STREAM. 

 Eev. Thomas W. Fyles, D.C.L., Hull, Que. 



Come, track with me this little vagrant rill. 

 Wandering its wild course from the mountain's breast; 

 Now with a brink fantastic, heather-drest, 

 And playing with the stooping flowers at will; 

 Now moving scarce, with noiseless step and Btlll; 

 Anon it seems to weary of its rest, 

 And hurries on, leaping with sparkling zest 

 Adown the ledges of the broken hill. I 



5 E.8. 



