No. 4.— On the Color and Color- Patterns of Moths and Butter- 
flies. 
By ALFRED Gorpsnonovan 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 Heliconidac, and of the Papilios of 
Tropical South America, and has been carried out under the direetion 
of my friend and instructor, Dr. Charles D. Davenport ; and the work 
was done in connection with one of the courses given by him in 
Harvard University in 1894-95. 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 ITeli- 
conidae, with special reference to the phenomena of mimiery ; 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 COLOR IN LEPIDOPTERA. 
I. CLASSIFICATION 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 (90-91) and Urech (793) have, however, given criteria for de- 
termining whether a color is due to a pigment or to some other eause. 
They sueceeded, for example, in dissolving out the eolor in many 
1 Contributions from the Zoülogieal Laboratory of the Museum of Comparative Zoöl 
ogy at Harvard College, E. L. Mark, Direetor, No. LXXIV, 
2 This paper was written in 1895 essentially asit now stands. 
