The Moths and Butterflies 
457 
yellow spots on the fore wings and two on the hind wings; besides there 
are some scattered red spots and some other yellow ones. The caterpillar 
is black, spiny, and banded with orange-red; it feeds chiefly on Chelone 
glahera , a kind of snakehead. On the Pacific coast the chalcedon, 
Melitaea chalcedon , is the most abundant checker-spot, although several 
•other species are common. It has black wings spotted with red and 
ocher-yellow; the spiny black caterpillar feeds chiefly on Mimulus and 
Castilleja. 
The satyrs or meadow-browns are a group of fifty or more beautiful velvet- 
brown butterflies whose markings consist chiefly of eye-spots, large and small, 
on both upper and under wing surfaces. A number of species are abundant 
and familiar, but a majority live exclusively in mountain states, and especially 
in the west. The common wood-nymph, or eyed grayling, Cercyonis alope, 
(PL X, Fig. i), is the most familiar eastern and middle state species. 
A larger similarly patterned form, C. peg ala, is common in the south. The 
larvae of the meadow-browns feed on grasses, are pale green or light brown, 
and have the last abdominal segment forked. On the Pacific coast one 
of the most abundant autumn butterflies is the California ringlet, Cceno- 
nympha calijornica, a small buffy-white member of this group with small 
eye-spots only on the under side of the wings. A number of interesting 
butterflies related to the meadow-browns are found only on mountain-tops 
or in high latitudes (arctic region) the equivalent in life conditions of high 
altitudes. In the Rocky Mountains on the peaks of the Front Range (13,000 
feet altitude) I have struggled, gasping in the thin air, after beautiful frail 
little brown and grayish butterflies, (Eneis and Erebia. Far above timber- 
line on bleak mountain-tops, masses of broken granite overspread for great 
spaces with lasting snow, these hardy little flutterers live successfully. At 
the edges of the great snow-fields are patches of alpine flowers, fragrant 
dwarf forget-me-nots and buttercups, which furnish food and interest for 
them in the solitude of the high peaks. 
The mountain-top butterflies of the White Mountains, of the Rocky 
Mountains, and of the Sierra Nevada are closely allied; indeed individuals 
of the same species are found on the summit of Mt. Washington and on 
the crest of the Rockies, and nowhere between these two widely separated 
localities. The question as to how this interesting condition of things came 
about would be answered (by the student of distribution) as follows: In 
glacial times the species probably ranged clear across the continent. With 
the retreat of the great continental ice-sheet, while most of the butterflies 
followed it closely north, or became in successive generations slowly adapted 
to the temperate life conditions, some few probably followed up the slowly 
retreating local mountain glaciers. In time, therefore, the descendants 
of these arctic-loving species found themselves still under truly arctic con- 
