44 DECEPTIVE COLORATION. 



bird became a conspicuous dark object against a "white 

 background, it took wing on the first suspicion of danger. 



I could mention many other similar instances, but the 

 careful observer will soon find them included in his own 

 experience. 



Deceptive, or, as Poulton terms it, " aggressive " col- 

 oration is perhaps best illustrated by coftimon Flycatchers 

 {Tyrannidw). Although these birds live in and about 

 trees, they are, as a rule, quietly attired in olive-green or 

 olive -gray, and are quite unlike the brilliantly q\q.6., fruit- 

 eating Tanagers, Orioles, Parrots, and other birds that 

 may be found near them. Insects are therefore more 

 likely to come "within snapping distance than if these 

 birds "were conspicuously colored. In the same manner 

 "we may explain the colors of Hawks, "which are never 

 brightly plumaged. 



It is well kno"wii that many arctic animals become 

 vi^hite on the approach of wintei*. With Ptarmigans 

 this is doui)tless an instance of protective coloration, but 

 the Snowy Owl, who feeds on the Ptarmigan, may be 

 said to illustrate deceptive coloration. 



Recognition, signaling, or directive colors have, with 

 more or less reason, been made to include many different 

 types of markings, of which I shall mention only those 

 that are conspicuously shown in flight or by some move- 

 ment. Such are the white outer tail-feathers of Juncos, 

 Meadowlarks, Towhees, and many other birds, and cer- 

 tain wing and rump patches, which are noticeable only 

 when the bird is on the wing. Markings of this kind are 

 supposed to aid birds in recognizing others of their kind, 

 their special use being to keep the individuals of a family 

 or flock together, so that when one starts the others can 

 I'eadily follow. The theory is open to objections, but 

 these so-called recognition marks are so often found among 

 birds that they doubtless are of some use, though their 



