tinued_ upward by the bird's dark, obscurely mottled body, terminating in the 

 broad, flat head. This mimetic attitude is completely effective in the twi- 

 light or moonlight, when the "Poor-me-one" uses a stump- top as a look-out 

 perch, whence it launches forth on short flights after aerial insects, soon 

 sailing back to cap the same or sometimes a neighboring stub. There can be 

 no doubt as to the completeness and importance of the mimetic function of 

 the "Poor-me-one's" pecuhar perching-habits. The mimicry, however, is 

 mainly positional, or attitudinal, for it is not supported by any very particular 

 developments of the bird's form or markings. The bird's mottled pattern, 

 to be sure, is less exquisitely fine than that of many nearly related goatsuckers, 

 and hence less well fitted to serve the full obliterative function of background- 

 picturing, while it must greatly help the stump-top mimicry, especially in a 

 dim light. " Poor-me-ones " have been found roosting in the daytime on the 

 tops of stumps, in the characteristic erect attitude, and in these cases they 

 were certainly "making a bid" for mimicry, in which both color and mark- 

 ings played a part. But it is likely that their roosting-habits vary somewhat, 

 as I know that their nocturnal perching habits do. They have a strong pref- 

 erence for naked stumps, but I have more than once seen them sitting in the 

 moonlight on horizontal leafy boughs, and even perching lightly among the 

 slenderest twigs at the very tips of the branches. Assuming that there is 

 equal irregularity in their diurnal roosting habits, as we may pretty safely 

 do, it follows that they must often be so situated that the obliterative function 

 of their coloration comes fully into play. Indeed, there can be no doubt of 

 this, as they are equipped with a complete, though slight, obliterative shading, 

 which hinders rather than helps the mimetic effect; and their markings, though 

 relatively, somewhat crude, yet partake largely of all the elements of back- 

 ground-picturing. But, from all that we yet know of the habits of this in- 

 teresting bird, it seems probable that it profits at least as much by out-and- 

 out mimicry (in effect) as by obliteration. This is the most pronounced case 

 of the kind that we happen to know of. Others equally remarkable exist, 

 no doubt; but they are rare enough to be fairly called anomalous. On the 



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