THE BROWN CQTTON-BUG. 77 



April 1. A specimen confined on a peach tree deposited 2 egg- 

 batches, containing in all 44 eggs, before the middle of May, 1906. 

 Nymphs which hatched from one of these batches were in the second 

 instar on May 13, but, as they disappeared soon after, definite informa- 

 tion concerning the appearance of adults of the first generation was 

 not obtained. From this and other records of eggs of this species 

 collected in the spring of 1906, however, it can be safely considered 

 to be between the 1st and the middle of June. A comparative study 

 of the developmental periods of various Pentatomid bugs which have 

 been under the writer's observation leads to the belief that it is 

 probable that in the cotton-producing States a maximum of ^Ye 

 generations per annum is possible, although four generations is 

 doubtless a more common number, and three generations the most 

 common of all. As with other Pentatomids whose egg-laying periods 

 may extend over several weeks with each female, it is improper to 

 speak of the generations as ''broods," for the reason that individuals 

 of from one to three different generations may and doubtless do occur 

 together after the maturity of the first generation. The brown 

 cotton-bug is most abundant in cotton fields during August and 

 September, but no rapid increase or decrease in its numbers during 

 the season has thus far been observed. 



DESTRUCTIVENESS. 



The usual association of the brown cotton-bug with other plant- 

 bugs in the cotton fields has made advisable the general consideration 

 of damage to cotton bolls resulting from the attacks of this and certain 

 other species, which has been given in the introductory pages. The 

 similarity of the feeding habits of the various Pentatomid bugs which 

 attack cotton bolls indicates that the studies made concerning the 

 individual destructive capabilities of the conchuela are fully appli- 

 cable to the other species. Fortunately the brown cotton-bug has 

 not as yet shown itself likely to appear over large territories in such 

 abundance as has the conchuela. It has been observed in limited 

 areas comprising only a few acres each, in numbers which caused 

 destruction of the majority of the bolls, but thus far experience has 

 shown this species to deserve the importance herein given, not on 

 account of sporadic outbreaks in excessive numbers, but through its 

 fairly constant and widespread occurrence throughout a large and 

 important cotton- growing section. 



NATURAL ENEMIES. 



Species of Pentatomids of the genus Euschistus appear to be 

 unmolested by Tachinid parasites. Examination of hundreds of 

 specimens of species of this genus, including pinned material in col- 

 lections and live specimens in the fields, has not thus far resulted in 

 the finding of evidence of parasitism by these flies in any instance, 



