A CASE OF PERSISTENT MELANISM. 225 



individuals of one of our common beetles that were quite striking. 

 We have in the Willamette Valley, as in almost all other sections 

 of the country, the well-known rose curculio, Rhynchites bicolor 

 Fab., which feeds chiefly upon the buds and flowers of wild and 

 of cultivated roses. It will feed, however, upon a few other 

 plants, especially the buds of wild blackberries, which grow so 

 abundantly along the streams in western Oregon. 



This weevil is about one fourth of an inch long, and in all the 

 sections of the country where it has been observed outside of the 

 Willamette Valley is of a red color above; while the underparts 

 of the body, and sometimes the head and beak, are black. The 

 red in some instances extends forward so as to include the head 

 and beak. When viewed feeding on the roses, the dark under 

 surface of the body is largely concealed so that the weevil 

 appears almost entirely red. 



The red color of the dorsal surface is possibly protective to 

 the species when it is feeding on the petals of wild or cultivated 

 roses, as the color harmonizes with the red of many roses, and 

 for this reason might make the individuals much less conspicuous 

 objects to hungry birds and other enemies. 



I found feeding along with the red individuals of Rhynchites 

 bicolor Fab. individuals which were totally black. At first I 

 suspected that these black individuals were of a different species. 

 Upon looking the matter up I found that they had in a few 

 instances been collected, and were called Rhynchites czneus Fab., 

 a black species, which is common in the eastern part of the 

 country. 



During the summer of 191 3 I demonstrated that the two forms 

 would breed together in captivity. However, of the several 

 larvai that I obtained from the eggs deposited none reached 

 maturity. Following these experiments I made a critical study 

 of the characters of our two forms found in Oregon, and failed to 

 observe any differences in structure whatever, hence considered 

 the black ones only as melanic individuals of the common rose 

 curculio. In order to get the opinion of a specialist in Coleoptera, 

 I showed specimens of the two forms to Dr. Van Dyke, of the 

 University of California. He stated that the two were the same, 

 and that the black form found in Oregon was not the Rhynchites 



