ENTOMOLOGICAL NEWS 



[Jan., 'ii 



Standards of the number of eggs laid by Insects IX." 



Being Averages Obtained by Actual Count of the Combined Eggs 

 from Twenty (20) Depositions or Masses. 



BY A. ARSENE GIRAULT. 



13. BLATELLA GERMANICA Linneus. 



The egg-capsules used here were taken from living females 

 occurring in a kitchen of a hospital at Dunning (Chicago), 

 Illinois, September 15, 1910; they had all been rotated. When 

 the embryos neared perfectness they were dissected out and 

 counted. This procedure is not necessary, however, for the 

 outline of each egg is well denned exteriorly and their num- 

 ber is easily determined. As a rule there are an equal number 

 of eggs in both sides of any single capsule, hence the even 

 numbers shown in the table. 



Wheeler (Journal of Morphology, Boston, III, 1889, p. 292) 

 states that oviposition occurs at all times of the year. The 

 same author (Ib., p. 301) gives the average number of eggs 



* For the first eight of this series, see ENT. NEWS, 1901 , p. 305 ; 1904, pp. 2-3 ; 1905, p. 

 167 ; 1906, p. 6 ; 1907, p. 89 ; 1908, pp. 4, 383 ; 1909, pp. 355-357- 



