290 REPORT OP THE COMMISSIONER OF AGRICULTURE. 



to the attacks of parasites, especially Tachinicl-flies and Ichneumonids 

 of the genus Ophion and allies. 



Young cabbage-plants often suffer severely from cut-worms, and there 

 are one or two species — notably Mamestra chenopodii — which badly dam- 

 age the old plant by eating the leaves and boring into the head. All 

 or nearly all of the principal cut-worms will undoubtedly feed upon cab- 

 bage, but we shall here consider only those concerning which we have 

 absolute knowledge of their cabbage-feeding proclivities. The subject 

 of remedies will be taken up at the close of the consideration of the 

 different species. ^ 



THE DABK-SIDED CUT- WORM. 



(Larva of Agrotis messoria Harr.) 

 [Plate II j Fig. 6.] 



This insect was first described by us in the Prairie Farmer of June 

 22, 1867, and subsequently treated of in our first report on the insects 

 of Missouri (p. 74) as Agrotis cochranii, out of compliment to Mr. J. W. 

 Cochran, of Calumet, 111., who had made a number of interesting obser- 

 vations on this and other climbing cut- worms. Later, however, in ex- 

 amining his types in the collection of the Boston Society of Natural 

 History, we found it to .be a synonym of Harris's Agrotis messoria. 



Evidently an indigene of North America, Agrotis messoria is wide- 

 spread in the United States. It is very common in California, one of 

 the commonest of the climbing and garden cut- worms in Missouri, is 

 abundant throughout Illinois, Indiana, and Michigan, was first de- 

 scribed from Massachusetts, and doubtless occurs throughout the 

 States. It is found in Ontario and Quebec, though not commonly in 

 the last-named Province. 



While commonly found in the vegetable gardens of the Western and 

 Northern States, this cut-worm has gained its reputation chiefly as a 

 climber, and as injuring dwarf fruit trees. We have considered it at 

 length in this connection in the report just referred to. It seems by 

 preference to gut the blossom buds of dwarf fruit trees, and when these 

 are all gone it takes the leaf buds until every bud upon the tree is de- 

 stroyed. Seventy-five of these worms have been taken from a single 

 six-year-old fruit tree on a single night, and nearly as many more found 

 the ensuing night. Mr. Cochran says : " There is not an orchard upon 

 the sands of Michigan or the light timber openings of Indiana, or the 

 sandy ridges of our own State (Illinois), but that has suffered greatly, 

 many of them entirely ruined by its depredations. It is far more de- 

 structive to fruit trees than any other insect, infinitely more so than 

 the Canker-worm, but unlike the other depredators of our orchard trees 

 it is easily kept in check, and at small expense permanently eradicated." 



The natural history of this species is that normal to the group. It is 

 single brooded, the larva? hibernate, and the moths appear in July and 

 August, after a duration in the pupa state of a month or more. 



The larva ( Plate II, Fig. G, a) is somewhat more than an inch in length, 

 of a dingy, ash-gray color, with lighter or darker markings. The back 

 is light, and the sides are darker, and the customary warts are shining 

 black. The head and thoracic plate are of a shining, ash-gray color, 

 and the under surface of the body a dirty yellowish green. 



The moth is marked as shown in the plate, the colors being : Fore- 

 wings of a light, warm cinereous, shaded with Vandyke brown and um- 

 ber, the terminal space, except at apex, being darker and smoky j hind- 



