76 William B. H 



ernis 



That which is of principal interest in regard to this correlation 

 of life histories to the surf-producing storms is the brief interval 

 between the storms, represented by the factor 3 or 6, and this with 

 its relation to the days required for development with each species, 

 viz: Compsomyia about 9 days, Sarcophaga assidua about 12 

 days, Lucilia about 15 days, and Sarcophaga sarraceniae about 

 18 days. Further, it must be remembered that the life history of 

 each species for this locality covers a comparatively definite period, 

 which is a necessary consideration in this matter of correlation. 

 When eggs or larvae were collected, very little chance was involved 

 in predicting the date on which the imagines would appear. The 

 writer made use of this factor in his experiments with the three 

 most abundant species. It would also be useless to speak of a 

 correlation to the surf producing storms if the life histories of the 

 species studied here corresponded to the life .histories of the same 

 species in localities remote from a beach. From the literature 

 consulted the following data was secured relative to the latter. 



Compsomyia macellaria: Morgan ('90) gives (August 18 to 

 August 29-30) II to 12 days; Francis ('90) larval stage about a 

 week and pupal stage from g to i^ days, a total of from 16 to 21 

 days. 



Sarcophaga assidua: Howard ('00) gives (July 3 to July 25) 

 22 days, also (July 9 to July 18-26) g to ly days. 



Lucilia caesar: Howard ('00) gives (May 12 to 29) // days. 



Sarcophaga sarraceniae: Howard ('00) gives (May 12-30) 18 

 days; (July 2-29) 27 days; (June 6-17) 11 days; (June 13-26) 

 JJ days; (July 7-21) 14. days; (July 9-22) JJ days; (July 24 to 

 August 9-1 1 ) 16 to 18 days; Kellogg ('05) gives 10 to 12 days, 

 Howard ('02) 10 days. 



One can readily see from the above citations that there is a 

 marked variation in each species, and that these periods do not 

 coincide very closely (excepting the first period in the last-named 

 species) with the results secured in these studies. It must, how- 

 ever, be admitted that more extensive and systematic work should 

 be done relating to the question under discussion. 



Conditions as stated above may lead to the impression that egg 

 deposition is a direct result of the presence of food within tht 



