No. 4. — Oil tJie Color and Color-Patterns of JMoths and Butter- 

 flies} 



By Alfred Goldsbokougii Mayer. 



This research is an investigation of the general phenomena of Color 

 in Lepidoptera, and also a special account of the Color-Patterns of 

 the Danaoid and Acraeoid Heliconidae, and of the Papilios of 

 Tropical South America, and has been carried out under the direction 

 of niv friend and instructor, Dr. Charles B. Davenport ; and the work 

 was done in connection with one of the courses given by him in 

 Harvard University in 1 894-95. ■^ I am indebted to Dr. Davenport 

 not only for suggesting the subject, but also for his kindness in devot- 

 ing much time to a criticism of the results. 



The paper is divided into three parts. Part A contains an ac- 

 count of the general phenomena of color in Lepidoptera; Part B 

 is devoted to a special discussion of the color-variations in the Heli- 

 conidae, with special reference to the phenomena of mimicry ; and 

 Part C consists of a summary of those results which are believed to 

 be new to science. A Table of Contents is given at the end of the 

 paper. 



PART A. 

 GENERAL PHENOMENA OF COLOK IN LEPIDOPTERA. 



I. Classificatiox of Colors. 



We follow Poulton ('90) in dividing Lepidopterous colors into (1) 

 pigmental and (2) structural. 



(1) Pigmental Colors are due to the presence of an actual pig- 

 ment within the scales, and although such colors are very common 

 in the Lepidoptera, it is frequently very difficult to say off-hand 

 whether a given color is due to a pigment or to some structural effect. 

 Coste ('90-'9l) and L'rech ("93) have, however, given criteria for de- 

 termining whether a color is due to a pigment or to some other cause. 

 They succeeded, for example, in dissolving out the color in many 



' Contributions from the Zoological Laboratory of the Museum of Comparative Zool- 

 ogj- at Harvard College, E. L. Mark, Director, No. LXXIV. 



'This pajier was written in 1895 essentially as it now stands. 



