THE ORTHOPTERA OF MINNESOTA. 49 



the Brewer's Blackbird {Scoleophagus cyanocephalus); and 

 the Cowbird {Molothrus ater), all catch and eat locusts. 

 The first four are the most active ones, especially as long as 

 they have to provide for their young. At this period they 

 are making constant trips from nest to field and return. A 

 Yellow-headed Blackbird, distinguished by lacking a feather 

 in the left wing, made thirty-seven trips per hour to a field 

 adjoining the river, where it had its nest in a clump of cat- 

 tails. Strange to say, later in the season, the locusts took 

 revenge by eating off all the leaves and softer parts of the 

 cat-tails, thus exposing the nest. As soon as the young 

 blackbirds are able to follow their parents they all go lo- 

 cust-hunting. Owls and hawks also feed largely upon these 

 insects, as the balls voided hj them always contain num- 

 erous parts of locusts. Other birds no doubt also eat lo- 

 custs, at least the unfledged ones. Prairie chickens have 

 frequently been seen in the roads picking up locusts, and the 

 same can be stated of some rails. 



Animals also eat locusts, and the skunk grows fat upon 

 this food. Even gophers do not despise a dish offender lo- 

 custs, which is also to the taste of toads, frogs and snakes. 



VALUE OF LOCUSTS AS FERTILIZERS. 



Locusts contain a large amount of nitrogen, and when- 

 ever they are caught on a large scale this valuable fertilizer 

 ought to be utilized. Prof. D. N. Harper made an analvsis 

 of locusts given him for that purpose. He writes: "I re- 

 port herewith the result of my analysis of the locusts hand- 

 ed to me for examination as to their contents for fertilizing 

 ingredients. The locusts and the alcoholic liquor in which 

 they were preserved were evaporated to dryness at a tem- 

 perature of boiling water. They were then pulverized and 

 thoroughly intermixed, and portions taken for analysis. 



This resulted as follows: 



(per cent) 



Nitrogen 10.71 



Phosphoric acid soluble in water 1.52 



Phosphoric acid insoluble in ^vater 24 1.76 



