THE INSECTS OF JUNE. 201 



cocoon, in what may be called the semi-pupa state, during which 

 period the chrysalis skin is forming beneath the contracted and 

 loosened larva skin. We once experimented on a larva which 

 had just completed its cocoon, to learn how much silk it could 

 produce. On removing its cocoon it made another of the same 

 thickness; but on destroying this second one it spun a third 

 but frail web, scarcely concealing its form. A minute Ichneu- 

 mon parasite, allied to Platygaster, lays its eggs within those 

 of this moth, as we once detected one under a bunch of eggs, 

 and afterwards' reared a few from the same lot of eggs. A still 

 more minute egg-parasite (Fig. 244) we' have seen ovipositing 

 in the early spring, in the eggs of the Canker-worm. 



Among that beautiful family of moths, the Phala3nidaB, com- 

 prising the Geometers, Loopers, or Span-worms, are two for- 

 midable foes to fruit growers. The habits of the Canker worm 

 should be well known. With proper care and well-directed 

 energy, we believe their attacks can be in a great measure pre- 

 vented. The English sparrow, doves and other insectivorous 

 birds, if there are any others that eat them, 

 should be domesticated in order to reduce the 

 number of these pests. More care than has yet 

 been taken should be devoted to destroying the 

 eggs laid in the autumn, and also the wingless 

 females, AS they crawl up the trees in the spring 2 ^- Canker worm 

 and autumn to lay their eggs. The evil is usually E Sg-parasite. 

 done before thefarmer is well aware that the calamity has fallen 

 upon him. As soon as, and even before the trees have fairly 

 leafed out, they should be visited morning, noon and night, 

 shaken and thoroughly examined and cleared of the caterpillars. 

 By well-concerted action among agriculturists, who should form 

 a Board of Destruction*, numbering every man, woman and child 

 on the farm, this fearful scourge may be abated by the simplest 

 means, as the cholera or any epidemic disease can in a great 

 measure be averted by taking proper sanitary precautions. The 

 Canker worms hatch out during the early part of May, from 

 eggs laid in the fall and spring, on the branches of various fruit- 

 trees. Just as the buds unfold, the young caterpillars make 

 little holes through the tender leaves, eating the pulpy portions, 

 not touching the veins and midribs. When four weeks old they 

 creep to the ground, or let themselves down by spinning a silken 

 thread, and burrow from two to six inches in the soil, where 



