154 
plumage of the Upland Plover shows a 
“crass” pattern, a type common to 
many field- or upland-inhabiting species. 
Certain of the Plover and Sandpipers wear 
this plumage during the summer when 
they live among weeds and grasses, but 
lose it for one of pure and simple counter- 
shading when they winter along the shores 
and beaches. 
From these simpler and more obvious 
instances of obliterative picture patterns, 
we are led to explanations of the brilliantly 
colored and intricately marked plumages 
of birds like the male Wood Duck, Pea- 
cock and Paradise bird (Paradisea), 
or of such special markings and appen- 
dages as the speculum in Ducks, gorget of 
Hummingbirds, tail-coverts in the Re- 
splendent Trogon, etc., all of which, 
under certain vital conditions, are con- 
sidered to make or to aid in making their 
wearers inconspicuous. 
The prevalent white color of the birds 
of the open sea is believed to give “con- 
cealment against the sky above, from the 
eyes of aquatic animals below them.” 
But their young are both obliteratively 
shaded and marked. 
“Ruptive” or “Secant” markings are 
designed to prevent the appearance of 
solidity following too great uniformity 
of color, and they “break up” the bird 
by cutting it into pieces none of which 
will reveal the whole.  Oyster-catchers 
and Murres are examples of ruptively 
marked birds, while the lines on a Wil- 
son’s Snipe’s scapulars or stripes at the 
side of a Teal’s breast are secant markings. 
Such, in briefest outline, are the prin- 
ciples through the application of which 
Thayer seeks to explain the uses of color 
in animals. Of their importance there can 
be no question, and, whether or not one 
follows Thayer in believing them to be so 
universally applicable as to supplant all 
previously advanced theories in relation 
to animal coloration, one must be suffi- 
ciently impresssed by the character of 
Thayer’s actually demonstrated discov- 
eries to avoid judging him hastily when 
one cannot at once accept his conclusions 
as satisfactory. Moreover, the critic 
Bird - 
Lore 
should constantly bear in mind Thayer’s 
insistence on the importance of looking 
at an animal from the proper viewpoint, 
whether it be that of foe or food; and 
for his warning there is abundant need. 
We are so prone to regard things from the 
level of our own eyes that we do not 
realize the absolute necessity of taking 
the position of Hawk, grasshopper, frog 
or fish as circumstances require. 
Few men have devoted as much time 
to this subject as Thayer; possibly no 
man is better fitted to grapple with it. 
Without hesitation, we admit the truth 
of his contention that the painter’s 
peculiar and specially developed gifts 
are required to appreciate at the full 
many facts in relation to animal colora- 
tion to which the average naturalist 
may be blind; but we, in turn, maintain 
that the problem should be presented by 
the naturalist. Through the exercise of 
his equally peculiar gifts, the animal must 
be studied in nature, its haunts examined, 
its foes and food ascertained, its need 
for concealing coloration learned, and all 
the significant details of its habits and 
actions under certain conditions recorded, 
before he ventures to ask for an explana- 
tion of the use of this color or that mark- 
ing. 
Fortunately, both Thayer and his son 
are naturalists, and are thus doubly 
equipped for the task they have under- 
taken. Still, we cannot but feel that their 
work as a whole would have carried far 
greater weight had it been based exclu- 
sively on their own field experience. 
After weeks of close association with the 
American Flamingo, for example, we do 
not believe they would have attempted 
to explain its colors by the wholly imagi- 
nary plates and hypotheses which they 
have presented; and we fear that it is 
such cases as these which will unde- 
servedly weaken the value of the Thayer’s 
work with those who have known inti- 
mately in nature species which they have 
never met, but the significance of whose 
colors they seek to explain. = 
Every real student of animal coloration 
will, however, recognize the great value 
