green, the hrgc warts or tubeicles on the top of the third and fourth seinnents are cnriil red, 

 the remainder are yellow oxccptini; those ou the second imd terniimd sejiments, which, in 

 common with the smaller tnbercles along the sides, arc blue. During its growth from the 

 diminutive creature as it escapes from the egg to the monstrous-looking full grown sjiccimen, 

 it consumes an immense amount of vegetable food ; and especially as it ajiproaches maturity 

 is this voracious appetite apparent. Where one or two have been placed on a young apple 

 tree, they will often strip it entirely hare before they have done with it, and tlius prevent the 

 proper ripening of the wood entailing damage to the tree, and, sometimes, cndangerini; its lile ; 

 hence, during their season, tliey should be watched for and di'stroyed. During the winter 

 months, their cocoons may be looked for, and removed in time to check their lurther spread. 



The natural increase of this insect being so great, wise provisions have been made to 

 keep it within bounds. Being such a conspicuous object it sometimes forms a dainty meal 

 for the larger birds ; there are also enemies wliich attack the egg and young larva; and besides 

 these there are severd parasites which live within the body ot the caterpillar and destroy it 

 before reaching maturity. One of the largest of these parasites is the lona; tailed Ophion 

 (Op/lion macrurum, Linn.) Fig. 20 (after Riley). This is a lariic yellowi.sh lirown Ichneumon 

 Yg 20 fly. ^id is perhaps one of the commonest parasites .affect- 



ing the cecropia. The female ol this fly depo.^^its, ac- 

 cording to Mr. Trouvelot, from eight to ten eggs U|ion 

 the skin of her victim. These eggs soon hatch into 

 yoiini; larvre which e.it their way through the skin i.f 

 the caterpillar, and at once begin to feed upon the fatty 

 parts within. As only one of these parasitic larv» can 

 find food sufficient to mature, the rest either die from 

 hunger or arc devoured by the strongest survivor. 



Mr. Kiley, in Am. £>it.,Yo\. II., says, "After 

 the Cecropia Worm has formed its cocoon, the para.^itic 

 larva which had hitherto fed on the fatty portions of its 

 victim, now attacks the vital parts, and when nothing 

 but the empty skin of the worm is left spins its own 

 cocoon, which is oblong oval, dark brown inclining to 

 bronze, and spun so closely and compactly, that the 

 inner layers when separated have the appearance of gold beater's skin. If we cut open one of 

 these cocoons soon after it is completed, we shall Hnd inside a large, fat, legle.«s grub. Fig. "21, 

 Fio. 21. which sometimes und<'rgoes its transi'onnations and is^sues 



as a fly in the fall, but more generally waits until the 

 following; spring. 



" The Ichneumon Fly, last mentioned, usually cau-es 

 a dwarfed appearance of the worm which it infests, and 

 parasitizrd cocoons can generally be distinguished from 

 healthy ones by their smaller size. The larva; of the Ta- 

 chinaFly which we now introduce to our readers, as parasitic on the Cecropia Worm, seem to 

 produce an exactly opiiosite effect, namely, an undue and unnatural growth of their victim. 

 In the beginning of September, 1866, we received an enorniouF. Cecio|iia Worm. It mea- 

 sured over four inches, was a full inch in diameter, and weighed nearly two ounces, but.like 

 many other large s])eciniens wliich we have since seen, it was covered with small oval, opaque, 

 w hite egg-aliell.s, clusters of four or five occurring on the back of each .S(><rinenl invariably 



depo.sited in a traver.se direction. The skin of the worm was 

 black, where the young panusites had hatched and penetrated. 

 Tlie large worm sixm died and rotted, and in about twelve days 

 a host of maggots gnaweil their way through the putrid skin. 

 These maggots averaged about one-half ineh in length, and in 

 form were like those of the common lUow-fly. The head 

 was attenuated and retractile and furuisiied with two minute 

 curved hooks, and the last segment was squarely cut off, slightly 

 concave and with the usual two spiracles or br(>athing holes 

 which this class cf larvae have at their tails. Their colour was 

 of a ti-auslucent yellow, and they went into the gi-ound and 



