154 The American Naturalist [F 



was not moistened in some way. Whether this must be from the 



; tongue or lips in all cases is a question \ 



r be considered 



not yet settled. Professor H. Osborn, of Iowa, is disposed to believe 

 that the young do not hatch unless moistened by the horse's tongue ; 

 that the young grubs generally die in the eggs if left for 35 to 40 days ; 

 and that they are not commonly ready to hatch until from 10 to 12 



Fossil Butterflies.— Fossil butterflies are the greatest of rarities. 

 They occur only in tertiary deposits, and out of the myriads of objects 

 that have been exhumed from these beds in Europe and America less 

 than twenty specimens have been found. The great body of these de- 

 posits is of course of marine origin, but at least thirty thousand spec- 

 imens of insects have been recovered from those beds which are not 

 marine. Over fifty thousand insects from the one small ancient lake 

 of Florissant, high up in the Colorado Parks have passed through my 

 hands, yet I have seen from them but eight butterflies. Each of these 

 belongs to a genus distinct from the others, as is also the case with all 

 or all but one, of the butterflies found at Radoboj, at Aix, and at Rott 

 in the European tertiaries. With two (European) exceptions, each re- 

 presents an extinct genus, and these two exceptions, Eugonia and 

 Pontia, are genera found to-day both in Europe and America. The 

 species, however, are all extinct. 



One would hardly expect that creatures so delicate as butterflies 

 could be preserved in a recognizable state in deposits of hardened mud 

 and clay. Yet not only is this the case, but they are generally pre- 

 served in such fair condition that the course of the nervures and the 

 color patterns of the wings can be determined, and even, in one case, 

 the scales may be studied. As a rule they are so well preserved that 

 we may feel nearly as confident concerning their affinities with those 

 now living as if we had pinned specimens to examine; and generally 

 speaking the older they are the better they are preserved.— S. H. Send- 

 der in Frail Children of the Air. 



Origin of European Butterflies.— Mr. W. H. Bath in discus- 

 sing 4 the effects produced by the glacial period upon the distribution 

 and diversity of European butterflies says: As the result of his inves- 

 tigations Ernest Hoffmann asserts that of the 290 species of Rhopalo- 

 cera inhabiting our continent at the present time, no less than 173 were 

 originally derived from Siberia. If this was the case, and it seems very 



* The Entomologist, XXVIII, 247. 



