PACKARD] THE COTTON ARMY-WORM. 777 



scientific standpoint, as it is a matter of national interest to arrest the 

 immense annual loss resulting from the attacks of the army-worm. 



As to the original habitat of this insect there is some question. Mr. 

 Grote believes that it is "an imported insect, and not indigenous to the 

 Southern States." He claims that, as in our climate cotton is an intro- 

 duced plant, and has become an annual, the cotton-worm has been im- 

 ported with it. As he says : " The first herald of the cotton- worm I have 

 found to be always the flight of the parent moths. These would come 

 to light in houses, and in a few days thereafter I found the young worms 

 on the plants. This, in Central Alabama, was in June or July, and 

 l^reviously I had always heard of the appearance of the worm to the 

 Bouthward. Before it, the cotton in my vicinity had shown no signs of 

 worm, and, had any existed in the country, it must have showed itself 

 during the preceding three months, while the young cotton-plants were 

 growing. In favorable seasons the broods were successive until frost, 

 and the death of the cotton-plant. Where food failed on one plantation 

 the worms wandered to another, and not till then. The first brood in 

 one locality is irregular, skipping some plantations, invading others. 

 Again, I have noticed that, while there was yet leaf enough left, and 

 the season yet warm, whole sections would be forsaken by the freshly- 

 disclosed moths. There is no doubt on my mind that the cotton-worm 

 has a yearly migration northward, from the facts in the case. The cold 

 weather finally kills the moths, without their being able to provide for 

 a further brood. I have noticed the moth in the fall as far north as 

 Canada and the great lakes, and on the coast of Maine.* Always ar- 

 riving there late in the season, it must perish; there is no food for its 

 progeny ; it is too late for it to retrace its steps." This supposed migra- 

 tion northward of the cotton army- worm is an interesting and practical 

 subject for further investigation. As yet I am hardly inclined to sup- 

 pose that this particular species should not live in all its stages where it 

 is now found, and I think that further research will prove that it is so. 

 It should be remembered that the caterpillars of a good many species of 

 this family do not hatch out until toward midsummer, for example, 

 the northern army-worm. Its larva should be looked for in the North- 

 ern States where it occurs, and, if found, the food-plant ascertained. It 

 is possible that the chrysalides have been carried north in cotton-bales, 

 but under the circumstances in which I have seen the moth flying on 

 an island in Salem Harbor, I do not doubt but that the caterpillar will 

 be found. I have taken several specimens of this moth on Coney Isl- 

 and in Salem Harbor. Mr. Edward Burgess informs me that it flew 

 aboard his yacht in Boston Bay, September 9, 1873. Mr. Grote records 

 it from Buff'alo, X. Y., and Mr. Riley from Chicago. 



In the accompanying map showing the area of distribution of the cot- 

 ton army and boll worm, I have indicated the area in which it is per- 

 manently destructive, being the cotton-growing portion of the Southern 

 States, taken from Walker's Statistical Atlas. 



Description of the moth. — Pale brown, with a slight reddish tinge ; hind wings some- 

 what paler. Fore wings with three indistinct irreguhulj^ scalloped reddish lines, the 

 basal one on the inner third of the wing composed of four or five scallops ; the second 

 is situated deyond the middle of the wing, and branches out behind the middle (trans- 

 versely) of the wing, and sends a branch just beyond the di^cal dot, forming a third 

 line. The scallops differ in size, but the line curves out most just below the costa, and 

 again opposite the discal spot, which is large, dark, conspicuous, obliquely oval, and 

 centered with two unequal bluish spots. Expanse of wings, 1.55 inches. Salem, Mass., 

 Demopolis, Ala., and Waco, Tex,, September 5, October 12, and November 15, — (Bel- 

 frage.) 



* This is most probably a mistake for Massachusetts, as I am quite sure it has not 

 been observed north of Salem, Mass. 



