ONE HUNDRED THOUSAND FACTS FOR THE PEOPLE. 369 



from a tobacco factory will usually de- 

 stroy them. The Aphis also attacks the 

 plants when grown under glass, but they 

 are more readily destroyed than the Red 

 Spider ( Telaris), which insect is very de- 

 structive when numerous. 



The best preventive to the ravages of 

 the Red Spider is a moist atmosphere, 

 but when this cannot be allowed, flour of 

 sulphur should be freely scattered among 

 ihe plants or upon the soil near them. 

 The fumes of melted sulphur will make 

 quick work with them, but it requires 

 great care in its application, for should 

 the sulphur take fire and burn, the fumes 

 will destroy the plants as well. 



WHITE-MARKED TUSSOCK MOTH. 

 —During the winter little bunches of 

 dead leaves are sometimes found to be 

 quite numerous on our apple trees. They 

 are generally fastened to the twigs, and 



V ? 1 v 



Fig. 13. 



upon examination are found to contain 

 gray cocoons. The greater portion of 

 these cocoons have an egg-mass glued to 

 them, which is composed of numerous 

 round, cream-colored eggs, of about 0.03 

 diameter, and partly covered with glis- 

 tening white froth-like matter; while the 

 other proportion of these cocoons have 

 no such egg-mass. 



This insect seems to occur more or less 

 over the whole country, and we have re- 

 peatedly received its egg-masses during 

 the past two winters. It is, however, as 

 wo might expect from its nature, often 

 confined, like the Canker-worm, to partic- 

 ular orchards in a particular neighbor- 

 hood. It feeds upon different kinds of 

 trees, such as the elm, maple, horse-chest- 

 nut and oak, but it seems to prefer the 

 apple, the plum, the rose and the pear. 



REMEDIES."=-Dr. Fitch has described 

 two parasites, which attack this caterpil- 

 lar, and we are acquainted with seven 

 others, making in all nine distinct para- 

 sites, which prey upon this species. 

 24 



In collecting the cocoons in the win- 

 ter in order to destroy them, none but 

 those which have the egg-masses on them 

 should be taken, as all the others, either 

 contain the empty male chrysalis or else 

 some friendly parasite. From the fact 

 that the female never travels beyond her 

 cocoon, it becomes obvious that, since 

 the insect can only travel in the caterpilr 

 lar state, it would require over a century 

 for it to spread even a hundred miles. 

 Hence we may rightly conclude that it 

 has been introduced into different parts 

 of the country in the egg-state on young 

 imported trees. How essential it is then 

 to examine every tree in planting out a 

 young orchard, and how easy it is, with 

 the proper precautions, to forever keep an 

 orchard free from its destructive work. 

 As already stated, the young worms let 

 themselves down upon slightly jarring the 

 tree, and though after the third moult 

 they lose this habit to a great extent, yet 

 they may always be brought down by a 

 good thorough shake, and where they 

 have once invaded an orchard, this will 

 be found the most feasible mode of kill 

 ingthem; though prevention, by destroy 

 ing the egg-masses in the winter when 

 they are easily discerned, is infinitely the 

 best, and surest remedy against its at- 

 tacks. 



BAG-WORM, alias BASKET-WORM, 

 alias DROP-WORM. — Our shade and or- 

 namental trees are often defoliated by va- 

 rious insects, and we will give brief ac- 

 counts of three which have attracted our 

 attention during the past summer. Of 

 these, the insect whose transformations 

 are illustrated below, is by far the most 

 common and injurious. It apparently 

 flourishes better south of latitude 39 ° 

 than north of that line. Year after year 

 shade trees are planted, and year after" 

 year a great proportion of them dwindle; 

 and die, until at last the opinion very gen- 

 erally prevails among land-owners that 

 it is of little use to try and grow them. 

 Consequently they are not as generally 

 planted as they should be. 



Throughout the winter the weather- 

 beaten bags may be seen hanging from al- 

 most every kind of tree. Upon plucking 

 them many will be found empty, but the 

 greater proportion of them will, on being 

 cut open, present the appearance given at 

 Figure 14; they are in fact full of soft 



