EVOLUTION OF THE COLOR PATTERN IN THE MICROLEPI- 
DOPTEROUS GENUS LITHOCOLLETIS. 
By ANNETTE FRANCES BRAUN. 
CONTENTS. 
о еи УРОО Е кышы. чы кы T, 105 
ИМЕННО Ant OBSERVATIONS EU E а оо a Dora oO Cd 106 
(a) Systematic Position and Characteristics of Lithocolletis....................... 106 
(b) Color Classes Represented and Structure of Scales.......................... 109 
(с) Comparative Study of the Adult МагКїпрв................................. 110 
(d) Ontogenetie Development of the Color Pattern............................. 118 
1: Histor... PODER Loaded obras riu Dea EE 118 
CAN o атту MM Scc T CE 121 
SKODA E o uon оО АЕРУ ВИОРОТ ИС SO NEN 123 
S LH UD AO ООВ cs eoo о dedo hoe АДУ 141 
(e) Phylogenetic Development of the Color Райегп............................ 149 
Иа оос ЛРУ csp cou era ke relié erii e ИДИ Ин cd on с 160 
НОРУОТ ДОНИО E 164 
I. INTRODUCTION. 
The interest in a study of the origin of the many and complex forms of color 
pattern in insects lies mainly in the hope that such a study may give additional 
insight into the fundamental principles of evolution in general. With few 
exceptions, such as the work of Tower on Leptinotarsa, researches of this nature 
have been confined to the Macrolepidoptera, chiefly to the butterflies and higher 
moths. The Microlepidoptera, which are less advanced from the viewpoint 
of evolution, have been almost neglected. Yet, within this group, several of 
the older and larger genera afford excellent and ample material for such an 
investigation. То secure convincing data, a critical study, both ontogenetic 
and phylogenetic, must be made of the species of a large genus, in which the 
color patterns, while sufficiently diverse to indicate that a considerable degree 
of evolution has taken place, are still comparatively simple. 
The genus Lithocolletis fulfills to an extraordinary extent these require- 
ments; hence the following investigations were undertaken with the object of 
ascertaining the modes of origin of the various color patterns in this genus and 
the influences which have been operative in their evolution. The study of 
adult color patterns has extended over a period of several years; the observa- 
tions on pupal development were made during the summer of 1910. 
It is a pleasure to express to Prof. M. F. Guyer my appreciation of his 
many helpful suggestions during the progress of my work. 
