CONDITION OF SOIL MOST FAVORABLE TO HATCHING. 231 



toward the bottom whenever tbe tubes were turned mouth downward; 

 while in tin boxes, where the eggs were phiced at different depths in 

 the ground, the young never descended, even when they were unable 

 to ascend on account of the compactness of the soil above." 



WHERE AND UNDER WHAT CONDITIONS OF SOIL THE YOUNG HATCH 



MOST FREELY. 



As may be gathered from a series of experiments recorded in Chapter 

 XIII, the eggs will hatch under the most varied conditions. As a rule, 

 the soils and locations preferred by the female in ovipositing will be 

 those in which the young will most freely hatch, viz, comi)act and sandy 

 or gravelly knolls and hillsides, with a south or southeast exposure. 



The experience of 1877 (App. 18) shows also that hatching takes place 

 very freely in late-mown meadows or prairies, or grazed pastures, where 

 the exposure of the ground permits ready oviposition, and the warmth 

 of the sun. In dry, well-drained, and compact soils of a light nature 

 the eggs are much better preserved than in heavy clays and loams, 

 where they are more subject to mold and rot. The experience of 1877 

 is rather misleading on this point, and indicates the necessity of gener- 

 alizing, not from the experience of one, but of many years. The insects 

 were most numerous, and seemed to hatch most numerously in the low 

 lands and in sheltered situations along river-courses. The facts aie that 

 in such situations those which did hatch survived in larger proportions 

 than did those which hatched in more exposed places, because the former 

 were better protected from the cold rains and storms of spring. 



TIME OF HATCHING. 



Here, again, we cannot take the experience of any one year as a guide,^ 

 but find the necessity of generalizing from all past experience. In much 

 of the locust area there prevailed such late warm weather in the autumn 

 of 1376 that considerable numbers of the young hatched prematurely, 

 and such is very generally the case. We had also some unseasonably 

 warm weather in January and February, 1877, during which large num- 

 bers hatched. These all subsequently perished. During the latter part 

 of March and early in April the hatching was general, but there 

 followed a period of cold, rainy weather, which checked the hatching 

 and destroyed a large number of the insects that had hatched. May 

 and June were characterized by abundant rains and storms, alternating 

 with warm, sunny weather, causing tlie hatching to le irregular, and in 

 some cases quite retarded. It would not be incorrect, therefore, to say 

 (App. 18) that in one and the same neighborhood the hatching com- 

 menced on the 1st of February, and did not cease till the end of June, 

 thus covering a period of five months. Yet this is exceptional, and it 

 has been much more regular and the period more restricted in previous 

 years. 



Those eggs which are laid earliest the previous year will also hatch 



