No. 492] 



PINK INSECT MUTANTS 



777 



purplish. This specimen, which is somewhat smaller than the 

 green ones, was taken August 9 on Staten Island, by Mr. Joutel. 



What is the significance of these peculiar pink and brown forms 

 which appear so sporadically among our green Orthoptera and 

 Homoptera? As Scudder says, everyone who sees one of these 

 rare insects for the first time, "thinks at once of autumn leaves and 

 their changes from green to red, and notices that these grasshopper 

 cases all occur in the autumn, so far as known." But further 

 reflection soon leads one to doubt a conclusion based on such a 

 superficial analogy, for it is evident, in the first place, that the colors 

 of these insects must differ greatly from chlorophyll or other plant 

 pigments, and, in the second place, the occurrence of the pink 

 individuals during late summer may have no significance, since it 

 is only during this season that even those of the common green 

 phase reach full maturity. In this connection, Scudder (1901) 

 also calls attention to the occurrence of Cyrtophyllus roseu^ in 

 tropical Costa Rica. 



There is, however, another fact hitherto unrecorded, which 

 seems to me effectually to dispel the notion that the pink phase 

 can be the result of temperature acting on the green pigment. 

 Some years ago, while I was sweeping the low vegetation in the 

 prairies of Wisconsin and Illinois for small Diptera, I took in my 

 net, on one or two occasions during July, a few pink larval and 

 nymphal katydids. Unfortunately I did not preserve the specimens 

 as I was at that time collecting Diptera only, but I retain in my 

 memory a vivid picture of the specimens. They varied from one to 

 two centimeters in length, and were either wingless or had small 

 rudiments of wings. They were pink throughout, like the adults 

 which I have seen since, and occurred sporadically in the same 

 sweepings with many specimens of the common green form. 

 These larval and nymphal individuals show that the pink katydid 

 is pink throughout life and this is in all probability true mutatis 

 mutandis of brown individuals and of the pink and brown Homop- 

 tera also. In other words, the pinkness or brownness are, like the 

 greenness, congenital or germinal characters and not the result of 

 environmental conditions. This being the case, we must incline 

 to the hypothesis advocated by Scudder and ShuU, that the pink, 

 and probably the brown individuals also, represent sports, or 



