26 



the maximum velocity of 40 miles an hour late in the afternoon. By 

 midnight the gale had decreased to 14 miles an hour, but increased 

 again rapidly, reaching a velocity of 20 miles an hour at 2 a. m., July 

 14, and 48 miles an hour at 8 40 a. m., then decreased to 30 miles at 

 noon, and 20 miles at 6 p. m. The direction of the wind varied from 

 south to southwest, distributing the moths toward the north and north- 

 east. Since the moths fly only by night, the day movement of the wind 

 is unimportant, but it is evident that during the nights of the 12th and 

 13th, the wind was effective in distributing the pest. Notwithstanding 

 this extensive distribution to the north and northeast, but few moths 

 have been found this year to the east, south, or west of the old colo- 

 nies. 



Although no extensive and critical search has as yet been made to 

 learn the exact aud entire distribution of the brown tail moth in Massa- 

 chusetts, it is known to occur to a greater or less extent in the follow- 

 ing cities and towns: Arlington, Belmont, Boston, Burlington, Cam- 

 bridge, Everett, Maiden, Medford, Melrose, Bevere, Saugus, Somerville, 

 Stoneham, Winchester, and Woburn. It is probable, from the very 

 nature of the case, that it already has even a wider distribution than 

 the above would seem to indicate. 



LIFE HISTORY. 



The moths are on the wing about the middle of July and each female 

 lays from 200 to 300 eggs in an oblong cluster on the under side of a 

 leaf near the tip of a branch, covering them with a dense mass of 

 brown hair from the tip of the abdomen. These eggs hatch early in 

 August, and the young caterpillars feed only upon the epidermis of the 

 leaves, causing them to turn as brown as though they had been burned; 

 and, as the leaves of these trees were devoured in the spring by the 

 preceding generation, the trees may be practically defoliated twice in 

 a season. The caterpillars also attack the fruit of the apple and pear. 

 While still young they begin to make a regular dwelling in which they 

 hibernate during the winter. This habitation is constructed at the 

 ends of the twigs, and is made by drawing together a few leaves, lining 

 them with silk and surrounding them with a mass of silken threads. 

 These tents are so firmly fastened to the twigs that they can rarely be 

 removed without using considerable force. 



The young caterpillars retire into these tents late in September and 

 hibernate daring the winter, emerging again about the middle of April. 

 They then feed upon the buds and later upon the leaves, devouring 

 their entire substance except the midrib, and in leaves having strong 

 ribs, like those of the maple, all the larger ribs are left untouched. 

 When the caterpillars are numerous, they devour not only the buds, 

 leaves, and blossoms, but even the green fruit. 



When the caterpillars are done feeding, which occurs from the first 

 to the middle of June, they transform to pupae among the leaves, spin- 



