214 
thp: condor 
Vol. XV 
thought process and to record the terms by which I seek to make a color name 
clear to my own apprehension. Accepting Ridgway’s arrangement and spacing 
of colors as a practical fixity, and referring all colors to the thirty-six-hue base, 
I designate the three diminishing tints of each local base as tint, half-tint, and 
r|uarter-tint, respectively; and the shades as shade, double-shade and triple- 
shade, respectively. This is not accurate in either case if we base our compari- 
son upon percentages of black or white, but it is practically correct if we appeal 
to the eye and that is what we are after. In like manner referring back to the 
normative hues all successive changes afifected by additions of neutral gray, 
I speak of gray (32%), double-gray (58%), triple-gray (77%), quadruple-gray 
(90%), and quintuple-gray (95.5%)' — the last two, of course, rarely required. 
In this way, the blue of a Valley Quail's breast designated in the text of Ridgway 
as Light Payne’s Gray, is thought of as the double-gray half-tint of Spectrum 
Blue : and the huffy of its lower breast, known as Light Buff, is related in 
thought to the Cadmium Yellow base by saying that it is the gray quarter-tint 
of that hue. It is thus clearly differentiated from “Cartridge Buff’ or “Tilleul 
Buff", which are as truly light-buffies, but which differ very materially in quality 
from the arbitrarily named Light Buff. 
In aiialyciiig a color, that is, in seeking to arrive at its proper designation, 
the reverse of this process is of the utmost importance. One first decides upon 
its basal or distinctive element, then estimates the relative admixture of gray, then 
turns expectantly to the appropriate column to determine the tint or shade. As 
a novice I should never by any possibility have guessed that a Valley Quail's 
Ineast is light Payne's Gray (indeed, I suspect I shall die in ignorance of the 
difference connoted by the names Payne's Gray and Puritan- Gray) , but I did 
guess first off, within one point, that it was a double-gray' quarter-'t'int of vSpec- 
trum Blue. A brief experience leads me to the belief that this logical process 
will always be followed, in practical disregard of arbitrary names. For this 
provision of a logical method of color inference, we are immeasurably indebted 
to our foremost living ornithologist, Robert Ridgway. 
PRELOIINARY REPORT UPON THE DISEASE OCCURRING AMONG 
THE DUCKS OE THE SOUTHERN SAN JOAQUIN 
VALLEY DURING THE EALL OF 1913 
By FRANK C. CLARKE 
Special Assistant, California Fish and Game Cemmission 
with eleven photographs and one diagram ey the author 
A bout the month of August, 1909, a fatal epidemic broke .out among the 
water birds, especially among the ducks, of the vicinity' of Soleta Lake, 
which lake, now dry, was situated about thirty-five miles southea.st of 
Tulare Lake. This epidemic, gradually spreading, raged throughout the hot part 
of the season till the cool weather of the fall, when it ceased. At this time Soleta 
Lake was quite stagnant, becoming' more so until it finally dried up some two or 
three years later. There were reports of a fatal disease among the water birds 
the year before, but little attention was paid to them. 
