° 1914 ] General Notes. 395 



of the first and last portions of this exposure would show. Although I 

 admit an unfamiliarity with Holboell's Grebe, if its methods of diving are 

 at all similar to those of other grebes and water fowl as a whole, the erect 

 head (if it is such) at the right side of this photograph appears odd. Ex- 

 cept when the birds employ a gradual sinking motion the head is thrust 

 forward and under when plunging and would not be in sight at the time 

 the rump was just disappearing. 



While I realize that half-tone reproductions do not show all the details 

 present in the photograph or better still, the negative, it seems that there 

 has been a misinterpretation of the evidence presented in this picture. A 

 much more logical interpretation would be that the so-called " ghost of the 

 wings " is nothing more than spray caused bj^ the bird's rapid plunge and 

 backward thrust of the feet which, being highly reflective, would quite 

 naturally appear light; the dark spots are shadows caused by the disturb- 

 ance in the water; and the grebe may be anywhere from a few inches to 

 several feet below the surface. — E. R. Kalmbach, Biol. Survey, Washing- 

 ton, D. C. 



Concealing Postures of Grebes. — On October 3, 1913, I was fishing 

 for bass in the tidal streams at Gibbstown, N. J. At one spot there was 

 a very shallow ditch some five or six feet in width, containing at the time 

 possibly six or eight inches of water. 



A Pied-billed Grebe (Podilymbus podiceps) had been observed in the 

 ditch about 11 a. m. and had made no special effort to get away with the 

 exception of one or two half-hearted dives, the water of course not being 

 deep enough. Early in the afternoon I walked down to the ditch with the 

 hope of getting a closer view of the bird. I could see nothing of it as I 

 gazed down upon the great mass of water lihes and other aquatic plant 

 life which abounded in the ditch, but after a moment I became aware of 

 an oblong body on the opposite edge of the ditch which up to that time had 

 been taken for a partly submerged and mud-covered leaf but which was 

 seen to be nervously moving at intervals and producing small circular wave- 

 lets on the water which in all other parts of the ditch was perfectly calm. 



I partly turned with the intention of taking another step to get a better 

 view, and was surprised to see a slender snake-Uke head a few inches in 

 front of the object I had been watching, turn slowly about on the surface 

 of the water and follow my movements. The facts were now self-evident, 

 and the object I had been watching was nothing more than the glossy back 

 of the grebe, which realizing the hopelessness of trying to escape by diving 

 had resorted to this method of concealment, flattening itself out, on the 

 surface of the water with its neck stretched out at full length. The wave- 

 lets were caused by a nervous movement of the feet beneath the water, 

 doubtless getting ready for the dash which was about to follow. 



I bent over in an effort to get a closer view, and the bird now evidently 

 frantic with fear made an elTort to sink itself breast first in the shallow 

 stream. The breast and neck were forced beneath the surface, while the 



