470 



sppayiug will have much effect uuless you begin it earlier iu the seasou, as the insects 

 are so protected by the leaves. — [June 1, 1891. J 



Parasite of Forest Teiit-caterpillar. 



I send you by mail some egg parasites bred from Forest Tent-caterpillar eggs this 

 spring. The eggs of this species are surprisingly free from parasites. I only got six 

 specimens of the species sent and no other parasites from about fifty egg clusters. I 

 inclose you Professor Townsend's description of two Tachinas which appeared in 

 Psyche recently. These were bred by me last fall. The smaller one was very abun- 

 dant ; over 80 per cent of the cocoons examined were infested. — [F. L. Harvey, 

 Orono, Maine. 



Reply. — * * * The small box arrived by the same mail and I was disappointed 

 to find that one of the specimens had disappeared during the journey. The other, 

 however, is a species of Tetrastichus, a genus in which we have an indefinite number 

 of undescribed species in this country which are very difficult to separate. 



Your species is probably undescribed. Tetrastichus is invariably, so far as we know, 

 hyperparasitic and the primary parasite is in your case, probably, a Telenomus or a 

 .Trichogranwia. — [June 2, 1891.] 



An Anthomyiid injuring Sugar Beets. 



I send to-day a few Sugar Beets planted in March and April. I find they have been 

 attacked with some new enemy, and I fear a dangerous one. We have 1,000 acres, 

 all very promising, but all are more or less afflicted with this disease. 



I send you some imported seed, thinking the pest was imported with the seed. 

 Three years ago all of the marsh mallow in the neighborhood of Watsonville was 

 similarly afflicted. * * * — ["W"^ y. Gaffey, Moro Cojo Ranch, Castroville, Cali- 

 fornia, May 22, 1891. 



Reply. — * * * Your beets have been attacked by the larva of some species of 

 Anthomyia closely allied to the Cabbage Maggot and Onion Maggot. The exact spe- 

 cies can not be ascertained without rearing the insect to the adult or "fly" state. 

 This insect could not possibly have been imported with the seed, and it will be very 

 interesting to know the nature of the crop i)reviously planted on the same ground, 

 or, if new ground, the nature of the vegetation before planting. None of the remedies 

 which have been heretofore suggested can be applied with any satisfaction on such 

 a large scale, and at this distance it is difficult to advise ; and probably the best 

 thing to be done will be to send you one of our California ageuts. — [June 1, 1891.] 



Remedies against Sand-flies and Mosquitoes. 



During two seasons of field work on the Geological Survey of Canada I have found 

 pyrethrura powder an excellent thiugtoburn in theteut to stupefy and kill mosquitoes 

 and black and sand flies. This powder is known by all druggists as " Insect Powder," 

 or as "Pyrethrum Powder," and sometimes as ''Dalmatian" or "Persian Insect 

 Powder." It is a perfect "God-send" to tired men in the field after a hard day's 

 work. Have also seen it used in the houses and stores of the Hudson Bay Company. 

 When you retire to your tent at night, or for a nap at midday, close all the sides and 

 the door of the tent, and burn about enough to cover a penny. Make the powder 

 into a little pyramid or cone, on top of bark, stone, tin, or any other article, and light 

 the tip with a match. It will smolder away, and the fumes will quite stupefy all 

 the mosquitoes in the tent. It is useless out in the open, but I have found "Hind's 

 Black Fly Cream" (prepared by A. S. Hind, pharmacist, Portland, Maine), an excel- 

 lent preparation for repelling flies, etc. It should be applied every few hours when 

 the flies are bad.— [A.M. Campbell, Box 126, Perth, Ontario, May 12, 1891. 



Reply. — * * * xhe use of pyrethrum which you describe is by no means new, 

 but your testimony as to its value is worth recording, and your recouimendation of 

 the "Black Fly Cream" is of value.— [May 1.5, 1691.] 



