14 THE ORTHOPTERA OF MINNESOTA. 



atid Spread thence to cultivated ground. Hon. Aug. Ander- 

 son, of Taylor's Falls, had two dozen hopper-dozers made 

 at that place and shipped to North Branch. Here these ma- 

 chines and about 100 gallons of kerosene oil were used with 

 good results for a short time. The farmers were advised in 

 the Isanti county papers to plow all fields in the infested 

 neighborhood. 



HOW LOCUSTS DEPOSIT THEIR EGGS. 



It is very important to know the manner and localities 

 in which eggs are laid b}^ the different kinds of locusts, be- 

 cause the only true and always successfuU remedy depends 

 almost entirely upon this knowledge. In former papers the 

 method of laying eggs by the Rocky Mountain Locust was 

 discussed, but it is best to repeat and enlarge upon what 

 was written at that time. The following figures will illus- 

 trate the method of egg-laying better than words. The 

 holes for the reception of the eggs are made by means of two 

 pairs of horny valves at the tip of the abdomen of the female 

 (Fig. 2, b and c). These open and shut rapidl}', and are 

 well adapted to execute this function. The female, pressing 

 the tip of her abdomen forcibly against /jT |yv 

 the soil, rapidly opens and shuts these I y ^\T^I/^77' 

 hard and pointed valves, and soon pushes '^^ Ifp^J/ 



them into the ground, thus drilling a hole. \JJ ■//y'^W'^ 



Fig. 3 illustrates this action, and the vari- fig. 2.— Rocky 

 ous positions assumed by the female are fountain Loc«st-a. 



i^ -^ anal characters of fe- 



plainl}^ indicated. In a short time nearly male showing horny 



ii J- -I j_i J. J J UJ valves, b, and c. (After 



the entire and greatly extended abdomen Rjiey). 

 is inserted in a little curved and more or less oblique cavity. 

 The legs are hoisted above the back during the operation of 

 drilling this hole, which requires more or less time, depend- 

 ing entirelv upon the condition and character of the soil. 

 As soon as the hole is finished, it is filled with a frothy and 

 mucous material. Professor Riley, in describing the method 



