FURTHER BIOLOGICAL NOTES ON THE COLORADO POTATO 

 BEETLE, LEPTINOTARSA DECEMLINEATA (SAY), IN- 

 CLUDING OBSERVATIONS ON THE NUMBER OF 

 GENERATIONS AND LENGTH OF THE PERIOD 

 OF OVIPOSITION. 



Bv Alec. Arskne Girault, Washixgtox, D. C. 



During 1907 I have tried to duplicate the obser\-ations on this 

 insect made in Georgia in 1906 (Girault and Rosenfeld, 1907), 

 and also to extend them in length of time, and in a measure have 

 succeeded in making some interesting and rather important 

 ones on its life history. These observations were made during 

 time not otherwise employed with the duties connected with a 

 field station, and hence they are not by any means as complete 

 and extensive as they should be and are necessarily more or less 

 desultory; they were also started somewhat late in the season. 

 But notwithstanding these, the facts learned I consider of impor- 

 tance, particularly as they tend to supplement some of the results 

 obtained by Tower (1906), which are not very well known to 

 entomologists. Not enough observations were made in most 

 cases to warrant final conclusions, and with this general warning 

 they are submitted for publication. 



The observations were made in the field laboratory of the 

 Bureau of Entomology, U. S. Department of Agriculture, at 

 New Richmond, Clermont County, Ohio, latitude 38 degrees, 

 48 minutes, north. 



SUMMARY. 



The following paper is based on observations made during a 

 single season on two pairs of hibernated beetles, interbred to a 

 second generation which reproduced, contrary to the results 

 obtained by Tower (1906) for normal beetles. A record of 

 oviposition is given for each generation, in the case of the hiber- 

 nated pairs exceeding the average recorded by Tower for normal 

 beetles. The length of life of the adults and the period of ovi- 

 position exceeds in each instance the average recorded by the 

 same author. In addition to observations on these points, a 

 number of records of the duration of the egg instar for dift'erent 

 dates are given, together with observations on habits of the larvae 

 and adults, and a few records of the duration of the post-embry- 

 onic instars. 



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