On Certain Grass-Eating Insects. 53 



increase of these insects is of no value. The same is probably- 

 true of other attractions, as molasses, and vinegar or beer, etc. 



Deep p/owing. — This was recommended as preventive of a 

 second attack. 



To preve?it injuries to cultivated crops. — In most cases the easiest 

 preventive is to surround these crops that are near the grass 

 with a strip one or two rods wide of some crop upon which the 

 larvae cannot feed, as potatoes. There may be instances where a 

 species has become firmly established in a cultivated field, because 

 the same crop has been grown for a series of years. A change to 

 some other crop upon which the larvae cannot feed would probably 

 rid the field of them. 



Methods of Study. — The study of this genus was begun by 

 the writer in July, 1892. Throughout the remainder of that sea- 

 son and during the season of 1895, continuous collecting supplied 

 the material studied. The first care was to secure fresh unrubbed 

 females which were heavy with eggs. These females were placed 

 in tightly corked homeopathic vials with a few blades of green 

 grass. Under these conditions they would live a week or more 

 and lay freely. Besides those in the vials a number of females 

 were usually placed in a breeding cage and observations 

 were made upon each lot. The most convenient breeding cage 

 was made by placing a lamp chimney over grass growing in a 

 small flower pot ; the top of the lamp chimney was covered with 

 muslin. The pot was placed in a larger one and packed with 

 sphagnum moss to prevent undue drying. In such a cage very 

 nearly natural conditions were seciired. The eggs in the vials 

 were subject to daily observations and when they hatched the 

 larvae were described, some preserved in alcohol, and the rest 

 placed in a cage. During the larval existence frequent observa- 

 tions were taken and full notes were made at the time of obser- 

 vation ; whenever practicable, drawings were made. During the 

 winter of 1892-93, all the larvae died from some unknown cause. 

 On this account it has been impossible to complete the round of 

 life of the species studied. 



In 1 889, the Entomological Division of the Experiment Station 

 ran six trap-lanterns throughout the season, and during the 

 season of 1892 one. From the material taken in these trap-lanterns 

 the periods of flight have been worked out and the number of 



