3t*i 



AMERICAN FORESTRY 



the entire time, taking to flight only when persist- 

 ently disturbed. At night they were restless, especi- 

 ally on rainy nights, when they fluttered up and 

 down the window-panes. By not gathering any on 

 three consecutive evenings, on the morning of the 

 fourth day there were no fewer than eighty-three of 

 them on the window, a good proportion of which were 

 females. 



The eggs are very small, of a bright pale green color, 

 and were deposited in patches. At their margins, these 

 patches were irregular, the largest one covering an area 

 of about a square inch. In a few cases a female would 

 deposit a small patch of her eggs on the wings of an- 

 other moth which had got- 

 ten beneath her. In about 

 ten days, these layers, all 

 sticking fast, were seen to 

 change color, becoming a 

 pale, whitish yellow. No 

 attempt was made to en- 

 courage hatching. 



In his "Field Book of 

 Insects," Frank Lutz says : 

 "The unsightly nests of the 

 Fall Web-worm, made in 

 late summer, are frequent- 

 ly confused with the spring 

 tents of Malacosotna ameri- 

 catia. The nest of cunca 

 has a lighter texture, and 

 covers all the leaves upon 

 which the colony of larvae 

 are feeding ; it occurs on 

 more than a hundred dif- 

 ferent kinds of trees, apple 

 and ash being among the 

 favorites." Fall nests of 

 the larvae of this moth have 

 never been seen by the 

 present writer in the Dis- 

 trict of Columbia; but that 

 may be due entirely to the 

 fact that no special search 

 has been made for them in 

 this section of the country. 

 Lutz points out and figures "the great varability which 

 exists in the markings of both larvae and adults." 



Of "pallida" of Packard he says: "The larvae are 

 social in their habits, and spin great webs upon the 

 foliage of almost all kinds of deciduous trees in late 

 summer and fall, and do a great deal of damage to 

 orchards and nurseries. The insects pupate in loose 

 cocoons, in crannies, and even under the loose surface of 

 the soil. The species ranges over the United States 

 from southern New England and New York to Texas 

 and further west." 



All the insects raised by the present writer had black 



TWO SKELETONIZED LEAVES OF THE RED MULBERRY 



Fig. 3. These show the work of the smallest fall web-worms, with a 

 number of the moths of this species on the sycamore leaves to the 

 left. These moths are all from life, reduced one-third in size; the 

 males are the smaller ones. 



account we have ot the Fall Web-worm is the one that 

 the late Professor C. V. Riley gave us in his brochure 

 entitled, "Our Shade Trees and Their Insect Defolia- 

 tors." Professor Packard reproduced this in full, in- 

 cluding the cuts, in his "Insects Injurious to Forest and 

 Shade Trees," which appeared in the Fifth Report of 

 the United States Entomological Commission. This re- 

 port is a very valuable one, and should be consulted by 

 those interested in the protection of a great many of our 

 trees, a list of 108 different kinds being presented, upon 

 the leaves of which the Fall Web-worm feeds. In this 

 list care has been taken to show the percentage of defolia- 

 tion done by these larvae in any particular species of tree. 



Riley's report contains 

 some very instructive illus- 

 trations. One gives the 

 "Ravages of the Web- 

 worm on poplars on one 

 side of a Washington 

 street, and exemption of 

 maples on the other." Here 

 we see, on Fourteenth 

 Street, late in September, 

 a row of large poplars 

 stripped almost entirely of 

 their leaves ; and we have no 

 reason to believe that such 

 a calamity may not occur 

 again. Indeed, the very 

 '.arvae described here may 

 be some of an advance 

 ^uard of the Fall Web- 

 worm moth, which another 

 season may be in Wash- 

 ington in millions. 



The smaller cuts in the 

 body of Riley's account 

 give a specimen of the Fall 

 Web-worm moth in posi- 

 tion on a leaf laying eggs, 

 with nine of the eggs en- 

 larged ; then we have a 

 dark larva of the moth 

 seen from the side ; a light 

 larva from above, with two 

 views of the pupae and the upper view of a spread moth. 

 Finally, there are ten cuts of wings from "a series of 

 moths showing the variation from the pure white to 

 one profusely dotted with black and brown." 



It is further stated that "the caterpillars of this moth 

 have quite a number of external enemies, which slay 

 large numbers of them." Several cuts are presented 

 illustrating these enemies, as one of the Rear-horse 

 (Mantis Carolina) ; the Podisus spinosus; also the pupa, 

 larva, and egg of the latter; an egg parasite; the 

 Meterorus hyphantria, with its cocoon a sort of small, 

 ichneumon-like insect, of which Riley says: "This insect 



antennae and immaculate wings and bodies, barring the has performed a very good service during the caterpillar 

 single specimen noted above. Perhaps the most formal plague, and has done much to check any further increase 



