1SS4.] floss on the American Rarcd Grebe.. lO 



grounds, from five to eight birds, evidently sentinels, sitting upon 

 the water with their heads high, ever upon the lookout and ready 

 to give the alarm, but slow to leave their station, — in fact never 

 leaving the little ba\', but taking good care to keep out of reach. 

 As soon as T passed bv, the birds, frightened from their nests, 

 would cautiously but quicklv return and join the sentinels, from 

 which point they would dive and come up within the rushes. In 

 no instance did I see them swim to or from their nests ; they may, 

 however, do so when not disturbed. 



As papers of this character are written solely to present the 

 observations and views of different writers in order that in the 

 end the history of the subject may be known and correctly given, 

 1 will say that Mr. H. W. Henshaw, in a paper of like chaiacter 

 (Am. Nat., V, 1S74, p. 243), states that he found the birds nesting 

 in similar lakes in Southern Colorado, but I think he is somewhat 

 in error in the conclusions reached, as given in the following 

 statement: "•The eggs were wholly concealed from view by a 

 pile of weeds and other vegetable material laid across. That 

 they were thus carefully covered merelv for concealment I can- 

 not think, since in the isolated position in which these nests are 

 usuallv found, the bird has no enemy against which such precau- 

 tions would avail. On first approaching the locality the Grebes 

 were all congregated at the further end of the pond, and shortly 

 betook themselves through an opening to the neighboring slough ; 

 nor, so far as I could ascertain, did they again approach the nests 

 dvu-ing mv stav of three days. Is it not then possible that they 

 are more or less dependent for the hatching of their eggs upon 

 the artificial heat induced bv the decaving vegetable substances 

 of which the nests are wholly composed .''" 



Surelv the birds have enemies in the vicinity, especially in the 

 Hawks and Gulls that would quicklv notice the eggs if uncover- 

 ed. In the grass, not fiftv feet from the nests I have described, a 

 Marsh Hawk ( Circus h?idsoiii7is) was found sitting upon fi\e 

 eggs. I also noticed se^'eral Hawks in the vicinitv, and several 

 Ring-billed Gulls {Larus deJmvaroisis) were skimming over 

 and about the lake. Further, I do not think it ••possible" to create 

 artificial heat from the slow decav of the vegetable matter com- 

 posing the nests, resting as the\ do in and upon the ice-cold water, 

 the eggs often touching the same. Before wading out to the nests 

 I removed mv boots and socks, and during the short time I was 



