THE SOUTilKHX IMNK SAWVKH. 49 



of tlie female. In the male this segment shows merely the anal open- 

 ing. In the female two liflohular tuherclcs are borne side by side on 

 this segment. 



SEASONAL HISTORY. 



There are four stages in the life of the sawyer, first, the egg (fig. 1 5) ; 

 second, the larva (fig. IG); third, the pupa (fig. 17): fourth, the 

 adult (fig. 14). 



In southern Mississippi the egg-laying period lasts from about the 

 first of March to the middle of October. In some cases eggs may 

 be laid earlier or later than the dates given, but the main activity in 

 egg-laying will be found tt) be com])risetl within this j)eriod. The 

 young larva^ hatcli from tlio eijgs in about five days after the eggs are 

 deposited." 



The length of time from the hatching of tlie young larva to the 

 time of nuiturity and change to the ])U])a a])pears to vary considerably 

 in different individuals. The coni})arative ])eriods of time .s])ent 

 in the larval and ])upal stages are not known. However, it is probable 

 that while the larval period may last for several months the ]>u]>al 

 period is not longer than two or three weeks. The length of time 

 occupied in passing from the egg to the adult stage varies greatly 

 in different individuals. It ap])ears that normalh" there is one 

 generation a year, with a partial second generation. Thus, on 

 August 12, 1908, the writer found larva^, pupae, and emergence 

 holes in the trunk of a tree which had been felled by storm April 24, 

 1908. The fact that the tree was felled on this date makes it certain 

 that the eggs of the sawyer were deposited subsequently. This 

 gives us a ])eriod of less than four months for the develoj^ment 

 from the egg to the emerged adult, in some indivitluals. Returning 

 to the same tree October 6, 1908, more emergence holes were found, 

 but there were still i)lenty of larviB in the trunk. Also, scattering 

 emergence holes were common at this date in other trees felled by 

 the storm of April 24, 1908, which were also abundantly infested 

 with larva?. On March 19, 1909, the writer again visited the tree 

 just mentioned, and found a good many larva* and on*' pui)a still 

 in the log. Thus it is seen what a great variation in the length of 

 time taken for development there may be among differ(>nt individuals 

 in the same log. The case of the sawyer in the Southern States 

 appears to be somewhat analogous to that of certain species of 

 Lepido])tera, a few adults of which emerge in the fall, while the 

 greater nund)er of the ])Ui)a' go through the winter before changing 



o This statement is biised upon observations made during the hottest part of the 

 summer. Possibly cj^.^ laid in ihe spring or fall might not hatch .«o quickly, as then' 

 would be less heat at those periods. 



