110 
It was on the summit of Lambert Dome, which is the dominant 
feature of the Tuolumne Meadows, that the photograph which accom- 
panies this article was taken. Lambert Dome is a solid mass of granite, 
rising a thousand feet above the Tuolumne River that skirts its base. 
It is a rock which has withstood the grinding of the glaciers of the 
past, and shows on its crest glaciated patches polished to a mirror- 
like surface. While the Sierra Club was in camp ‘across the river at 
the Tuolumne Meadows, Lambert Dome was the objective point of 
many short climbs. It was during one of these excursions that patches 
of sphaerella nivalis were found. To quote from my note-book under 
date of July 16th:—‘‘On the west side of Lambert Dome are patches 
of ‘red snow’. It looks as if carmine ink has been spilled over the 
snow. The snow-drift, splashed with red, is in the immediate fore- 
ground, the tall pines on one hand, and the precipitous sides of the 
Dome on the other inclose a vista of deep green tree-tops and meadow, 
through which meanders the silvery Tuolumne River. The purple 
foothills flank the snowy glacier-scarred peaks that pierce the sky: the 
whole is overhung with slowly drifting cumulus clouds.’’ It was 
under these picturesque circumstances that the first photograph of 
‘“‘red snow’’ was ever made in natural colors. 
One of the most prominent members of the 1911 outing of the 
Sierra Club was Dr. W. lL. Jepson, of the botanical department of the 
University of California. 
Upon request he furnished me this memorandum on_ sphaerella 
nivalis: ‘* “Red snow’, protococcus nivalis, or according to the latest 
nomenclature, is sphaerella nivalis. The cells are spherical and have 
no power of motion in the frozen snow, but in the summer, when the 
snow melts, the cells become vegetatively active, increase in size, and, 
after the fashion of the simple algae, divide into usually four, or six, 
or eight (or even two daughter) cells. These daughter cells escape 
from the original cell, and by means of rotating hairs at one end, they 
have the power of motion through the melted film of water, which fills 
the spaces between the particles of snow on a warm summer’s day. 
The cells secure their nourishment partly from the water, and partly 
from the atmospheric dust which always lies on the snowfield, and 
which becomes dissolved in the film of melted snow.’’ 
The color-plate of shhaerella nivalis, which forms the frontispiece 
of this volume of the transactions, is a direct reproduetion from the 
original photograph made by the Lumiere process in natural colors. 
The apparatus used in making this autochrom was a 314x514 camera 
fitted with a No. 1, Series Ifl, double anastigmat, F 6.8, 6 inch focus, 
diaphragmed down to f24. The autochrom was given an exposure of 
6 seconds, This relatively long exposure was necessary on account of 
