204 NEW YORK STATE MUSEUM 



potato, beet, spinach, lamb's quarters {Chenopodium alburn)^ smartweed, 

 buckwheat, willow, spruce, asparagus and corn. 



Though the insect is not abundant on all the plants mentioned above, 

 and probably feeds on certain of them only under exceptional condi- 

 tions, yet the Ust is so extended, including 29 species or varieties and 

 representing 18 natural orders, that it is very ditficult to say what the 

 caterpillars will not attack. It is probable that farther study would 

 show that the larvae feed on a number of other grasses besides those 

 recorded at the beginning of this notice. 



Distribution. This insect appears, from the record of its injuries, 

 to be widely and generally distributed over the United States and the 

 southern part of Canada. Its depredations have been reported from 

 most of the eastern states from Massachusetts to Florida, in many of the 

 central and western states, and in southern Calitbrnia and the state of 

 Washington. 



Natural enemies. Several parasites have been reared from this 

 insect. Ophion purgatum Say has been bred from this species by Mr 

 Caulfield. As this parasite is one which has been found attacking the 

 army worm, Leucania imipuncta Haw., in numbers, it is of importance to 

 know that it also preys on this species. Lim^ieria ajinidipes Cres. has been 

 reared from this Mamestra ( /;^^<?^/ /z/d". 1890. 3:17). Another parasite 

 which has been bred by several observers, is Mict'oplitis mamestrae Weed. 

 It has the peculiar habit of attaching its brown, ribbed cocoons between 

 the anal prolegs of its victim. Teleno?fius heliothidis Ashm. has been 

 reared from the eggs of this insect by Prof. Davis, who found that it 

 destroyed from two thirds to three fourths of most clusters. Dr James 

 Fletcher has reared two egg parasites, a Trickogramma and another black 

 Proctotrypid, in large numbers. Prof. Davis also records an attack on 

 the eggs of this species by two insects. The adult of Megilla maculata 

 DeGeer devours the eggs, shell and all, while the tarnished plant bug 

 (probably Lygtis pratensis Linn.) sucks out the contents and leaves the 

 shell nearly entire. The common toad is reported by Mr Kirkland as 

 feeding on the caterpillars. 



Remedies. The gregarious habits of the young caterpillars render 

 their destruction by hand picking comparatively easy. They can be 

 killed by spraying with paris green and water, at the rate of one pound 

 to 150 or 200 gallons. In cases where it is undesirable to poison their 

 food plants, the caterpillars can be controlled by the use of fresh pyreth- 

 rum, hellebore or kerosene emulsion. 



