REPORT OF THE ENTOMOLOGIST AXD BOTANIST 227 



SESSIONAL PAPER t-'o. 16 



2 lie Pupa. — The full grown caterpillar spins a cocoon of grayish silk so loose in 

 oonstruction that tho pupa may be socu through it. The pupa is S»e-eighths of an 

 inch long and dark brown in colour. It has yellowish-brown hairs scattered over the 

 abdomen and on the top of the thorax. The cocoons are by preference spun among the 

 leaves at the tips of branches, a dozen or more caterpillars frequently spinning one 

 web, within which each individual forms its own cocoon and changes to a pupa. The 

 cocoons are also found under fences and beneath the edges of clap-boards. A mass of 

 cocoons nearly two feet across was found in the cornice of a house by Mr. A. II. Kirk- 

 land. 



The Adult Moth. — The moths are pure white, with the end of the adbomen brown. 

 ]>oth sexes bear at the tip of the abdomen, but more conspicuously with the female, 

 a tuft of brown hairs, almost globular in form. This is the only moth occurring in 

 America to which this description applies, and it i^; therefore unmistakable. The 

 female expands about one and one-half inches and the male is smaller. The moths 

 fly in Xew England from the 1st to the 20th of July, the time varying with the season. 

 It is a night-flying insect, few being seen on the wing in the day time. Tho time of 

 greatest activity is from 10 o'clock to midnight. They are strong fliers and are 

 attracted to light. 



21ie Winter Wehs. — The webs in which the caterpillars pass the winter are very 

 characteristic, there being no other insect structures found upon trees in winter which 

 can be mistaken for them. Any web consisting of two or three leaves spun together 

 near the tips of branches and containing small brownish downy caterpillars in winter 

 time, must be those of the Brown-tail Moth. In early sprin^, as soon as the buds 

 begin to appear upon fruit trees, these young caterpillars, which are at that time one- 

 fourth grown, issTie from the nests and attack the leaf-buds and blossoms and later 

 the foliage of the trees upon which they have wintered. The growth of tho cater- 

 pillar is rapid; it reaches f\ill size and begins to spin its cocoon during the last half 

 of June, when it changes to a pupa and remains in this conrlition for about three 

 weeks before the moths appear. 



In addition to the above enemies, several other insects have been more abundant 

 than usual in certain localities. In Nova Scotian orchards two insects have been con- 

 spicuous by their numbers and injuries. The Whrite-marktd Tussock Moth, Hemero- 

 campa leucostigma, S. & A., and the Red or Rusty Tussock Moth, Notolophus antiqua, 

 L., have been widespread, and not only devoured the leaves of the tre&s, but did much 

 harm by gnawing cavities in the sides of the growing apples. Since the discovery of 

 the Brown-tail Moth in New Brunswick and Nova Scotia, a great many specimens of 

 the cocoons of Tussock Moths have been received for examination. These were found 

 to be so much infested by various parasites that there is every hope that tho injury by 

 these insects will be very small during 1907. 



Two other species which have been very much commoner than for many yeors, 

 are the Yellow-necked Apple-tree Caterpillar, Datana ministra, Drury, and the Red- 

 humped Apple-tree Caterpillar, Schizura concinna. S. & A. They are both large and 

 voracious caterpillars which feed in colonies and sometimes strip a whole branch of a 

 tree before their presence is noticed. I hav^e never known cither species to be. in suf- 

 ficient numbers to require any other treatment than tho cutting off of the colonies 

 and destroying them. A remarkable fact about the Red-humped Apple-tree Cater- 

 pillar is the very large proportion which are always found to be parasitized. This was 

 the case last season in Nova Scotia and was also observed in Maine by Miss Patch, 

 the State Entomologist. The parasite which does good work, is a small four- 

 winged fly about ^^ of an inch long, with a black body and red legs, prettily banded 

 with black and white. The eggs are inserted into the body of the caterpillar and the 

 grubs become fully developed before the caterpillars are half grown. They then spin 



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