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pleasant, moonlight nights in summer when the \\'inds are 

 iavorable their flights are continued long after nightfall. Not 

 unfrequentl}' have cases been mentioned by observers of their 

 flying after ten o'clock at night. These night flights seem to 

 be very much more frequent during dry seasons than in wet 

 ones; and in arid than humid regions. In fact da}' flights seem 

 to be rather the exception than the rule where the atmosphere 

 is normally very dr}'. On the contrar}', where the opposite is 

 the case the insects choose daylight b}^ which to make their 

 journeys. 



In taking a particular course it is not absolutely necessary 

 to have the wind direct. The locust cquall}' often flies quar- 

 tering with the wind, and sometimes nearly at right angles 

 with it. In spring the insects can and do move southward with 

 any wind that is north of east or west. On the return flights 

 any wind coming from south of these points of the compass 

 ^vill aid it ouAvard. Onh' "'Jiead' winds, then, interfere with 

 the migrations of our locust; and in many cases even these 

 are made use of by slighth^ changing" the course of flight. Very 

 high winds, Avhether blowing in the right direction or not, 

 cause the insects to drop to the ground. .Storms also have 

 the same effect upon moving mangas. 



Egg-laying. — The eggs of our locust are laid chiefl3Mn the 

 spring of the year by insects that have been full-grown for at 

 least eight or nine months and that have passed the previous 

 fall and winter as voladoras. In this respect it resembles the 

 large and closel}' allied North American Schisiocci'cd nmcri- 

 caiia which possesses a like habit. It will be noticed, however, 

 that a reference is made on a preceding page to eggs being 

 also laid during the months of January, February and March 

 in some portions of the Republic. Oar knowledge of the move- 

 ments and habits of the insect in those particular regions 

 is so limited that it is impossible to state definitely whether 

 there might not be a second brood in the north, or whether 

 these northern sw;irms are only another race in which egg- 

 laying occurs a few months later than in the more southerly 

 and less elevated regions. 



The female locusts when read}' to deposit their eggs usually 

 gather in large numbers at suitable places. They are invaria- 

 bly accompanied by the males which may remain in copula- 

 tion w^ith them to within a few moments of the commence- 

 ment of the burrow bv the female. 



