410 NATURE SKETCHES IN TEMPERATE AMERICA 



than a hundred of these locusts were seen. Of this number 

 twenty-se\en were swept into my net at random, with a view 

 to examination. A census of this series showed the following 

 ratio of color varieties: out of nineteen females seven were 

 green and twelve were brown (like the upper right-hand figure 

 of the plate illustration), while out of eight males all were 

 brown (like the lower right-hand figure in the same plate) . 



In Aj)ril the nymphs are found more than the adults. In 

 the lower left-hand corner of the plate illustration I have shown 

 a pale nymph cuticle against a dark background. This exuvia 

 or skin was shed by the adult female shown immediately above 

 it on the same plate but a few minutes before I j)ictured it. 

 On April "22, 190G, I found tiiree nymphs in the southern part 

 of Chicago at the border of an oak copse. Here they enjoyed 

 a life among the debris resulting from the decayed leaves, 

 and stems of herbage. A few days later these nymphs moulted 

 in my vivarium at home. In this region adults reach maturity 

 from aboJit the last of April to the second week in May. 



At Miller, Indiana, June fifth, I found a female laying her 

 eggs in (lamp sand at the border of a pond. When I approached 

 she had her abdomen buried (juite deeply. After I waited 

 about fifteen minutes she finally moved away from the place. 

 I proceeded very carefully to dig the earth away to one side 

 of the burrow and then it was found to be twenty-seven milli- 

 metres deep and at the bottom the eggs, twenty-five in number, 

 were laid in a compactly cemented mass. They were bound 

 together with a whitish mucus and there was quite an amount 

 of this substance lying above the eggs in the burrow. The 

 smaller poles or ends of the eggs were directed upwards, as is 

 usual with the Acridians. The eggs measured four and one half 

 millimetres in length and about one millimetre in width, and 

 they were slightly curved in their long axes. Both ends were 

 rounded, but the cej)halic or head end was slightly smaller than 

 the opposite one and further distinguished in the fresh eggs by 

 the very small, densely opaque, cap-like structure occupying the 

 extreme tip. There is but one brood of these insects, the young 

 hatching from these eggs passing the winter in the nymph state. 



In reference to the color varieties, McNeil mentions in 

 "Psyche" that the brown form "is the common one in the early 



