Feb. 1890.] 



AND OOLOGIST. 



19 



Nesting of the Pied-billed Grebe. 



1 noticed that in the September O. & O. 

 Mr. Win. G. Smith had an article on the nest- 

 ing of the Pied-billed Grebe {Poditymbiix: pod- 

 icep.s) in whicli he gave it as his ojjinion tiiat 

 this Grebe incubates its eggs by the warmth of 

 its own body rather than allowing them to 

 hatch by the heat being generated by the de- 

 caying vegetation which usually comi)oses the 

 nest. 



We should ;ill feel indebted to Mr. Smith 

 for this new information as it has hitherto 

 been supjiosed that the Grebe invaiiably relied 

 on the decaying vegetation to furnish the heat 

 necessary to hatch the eggs. 



At Minneapolis, Minn., I had ample oppor- 

 tunities to observe tJie nesting habits of this 

 bird, and in that locality, as far as my experi- 

 ence went, I found that the l)irds never sat on 

 the eggs in the daytime. Whether or not 

 they do so in the night 1 am unable to say. 



I have examined hundreds of their nests, 

 and in every case where the set was com- 

 plete the eggs were covered with the rege- 

 table matter. Incomplete sets of three, four 

 or five were . gener.ally found uncovered. 

 This is a good point for the decaying theory 

 it seems to me, as the birds did not want the 

 eggs to l)egin to incubate until the full com- 

 plement had been deposited. 



I have also noticetl that the deeper the 

 eggs are imbedded in the refuse matter the 

 more incubated they are, a fresh set having 

 just a tliin layer over them. 1 cannot ac- 

 count for this unless the layer first put on 

 loses its heat after a time, and more is hea])ed 

 on, for if we dig into it we find that the 

 deeper we go the warmer it gets; and per- 

 haps the Grebe realizes that it is best to be 

 certain that her already incubated eggs do not 

 become cold. But this is only theory and 

 will not be tolerated: facts are what are 

 wanted. 



I have never seen a (xrebe on her nest, al- 

 though I have often come suddenly and noise- 

 lessly ni)on it. At other times I have been on 

 the edge of swamps where the reeds were thin, 

 and 1 could see three or four nests at a time, 

 and although the birds were sometimes around 

 they were never on or very near them. I think 

 it will be safe to say that the Grebe does 

 not sit on her eggs in that locality, but re- 

 lies on the decaying matter to hatch them, 

 liet us hear from others on the subject. 



Geo. G. CanfwelL 

 Lake Mills, Wis. 



A Series of Eggs of the Prairie 

 Falcon, 



The eggs of the Prairie Falcon {Falrn niexi- 

 canuH) are very beautiful. They are subject to 

 great variation, and the series described below 

 does not contain all their types of coloration, 

 but is nevertheless well worthy of being placed 

 on record. 



Set I. April 6, 1888. Sargents, California. 

 Nest on ledge of rock, on a iirecipitous blufl'. 

 The eggs were laid on a few pieces of friable 

 rock. Five eggs, containing large embryos. 

 Ground color creamy white, speckled, spotted, 

 and clouded with vinaceons-cinnamon and 

 cinnamon-rufous. Two of the eggs appear 

 much lighter in color than the others, because 

 the markings consist almost wholly of specks 

 of vinaceons-cinnamon", and these are not close- 

 ly distributed over the surface; consequently 

 more of the ground color shows than in the 

 others. In two others the markings are of 

 cinnamon-rufous, and these also have cloud- 

 ings of the same color. The fifth egg has also 

 large spots and cloudings of cinnamon-i-ufous, 

 and is by far the handsomest in the set: l.i);") 

 xl.. 57: 2 00x1.60; 2.07xl..")S; 2.05x1. .58; 2.11 

 X 1.64. 



Set II. April 4. 1883. Near Mt. Diablo, 

 California. Eggs laid on sand in a small cavity 

 in a sandstone rock known as the "Mountain 

 Builder." Mt. Diablo is in Contra Casta 

 County, and the hole from which the eggs 

 were obtained was about sixty or eighty feet 

 from the base of the rock, but the rock was 

 near the brow of a hill two or three hundred 

 feet above the bottom of the canon, on a hill- 

 side so steep as to make the nest virtually sev- 

 eral hundred feet high. The distance from 

 the top of the jutting point of the rock to the 

 hole where the eggs were found was not more 

 than ten feet, and was reached by the collec- 

 tor being lowered by a rope. The cavity itself 

 was about two and a half feet in diameter and 

 extended into the rock nearly three feet. Five 

 eggs, incubation commenced. They are very 

 handsome, having a creamy ground color, 

 which is almost wholly covered with specks, 

 spots and cloudings of cinnomon and vinace- 

 (ms-ciunamon: 2.00x1.56; 1.09x1. .56; 1.98 x 

 1..59; 2.11 X1.5T; ].9:)xl..56. 



Set III. May 1, 1887. Sweetwater County, 

 Wyoming. Nest on rocky mound, along the 

 Big Sandy River. The eggs (two in number) 

 are very different from each other in ajjpear- 

 ance, one having a ground color of cinnamon 



