154 



Bird -Lore 



plumage of the Upland Plover shows a 

 "grass" 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 Hke 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 



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. 

 .\fter 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 the)' seek to explain. 



Every real student of animal coloration 

 will, however, recognize the great value 



