162 Journal New York Entomological Society. [Vol. xxvil. 



NOTES ON THE NORTH AMERICAN SPECIES OF 

 HIPPODAMIA (COLEOPTERA). 1 



By P. H. Timberlake, 

 Honolulu, T. H. 



The writer has been studying our North American species of 

 Hippodamia for several years past, and presents the results of his 

 studies at the present time as a solicitation for additional material 

 much needed to complete the work. Our species have been studied 

 from a new angle with gratifying result, namely by the aid of char- 

 acters residing in the male genitalia. The writer has carried on 

 extensive breeding work also with several of the species, which has 

 thrown much light on the extent of variation in the thoracic and 

 elytral markings. 



Before proceeding further it might be well to review briefly the 

 work of other writers during the last two decades. Colonel Casey 

 has produced two important articles 2 on our species, and has done 

 much in elucidating and describing not a few of the western forms. 

 Although his work can not be considered conservative and is not 

 entirely free from errors of identification it has done much to stimu- 

 late other workers. It is apparent now that some of his species are 

 merely forms or geographical races which may be recognized as 

 subspecies. Mir. Leng 3 on the other hand appears to the writer to be 

 somewhat too conservative in his treatment of the species so that 

 the actual status of our forms in a general way lies somewhere 

 between the extremes set up respectively by him and Colonel Casey. 

 Another important contribution to the knowledge of our species is 

 R. A. Johnson's " Determinate Evolution in the Color Pattern of the 

 Lady-beetles." 4 Mr. Johnson attacks the subject from the standpoint 

 of the experimental biologist and is much less successful in his taxo- 

 nomic treatment. On this account his treatment of Hippodamia con- 



1 Contributions from Experiment Station, H. S. P. A. 



2 Journ. N. Y. Entom. Soc, Vol. 7, pp. 61-169, June, 1899 ; Canad. Entom., 

 Vol. 40, pp. 393-421, Nov., 1908. 



3 Journ. N. Y. Entom. Soc, Vol. 11, pp. 35-45, pi. 4, Mar., 1903. 



4 Carnegie Inst. Washington, Publ. No. 122, pp. i-iv, 1-104, figs. 1-92, 

 June, 1910. 



