12 bikd's-nesting. 



neighbors, which by their actions they will often be- 

 tray to the collector who may be patiently watching 

 them." Again, birds, even when not of parasitic 

 nature, like the crow blackbird, will occasionally lay 

 their eggs — accidentally, as it were — in the nests of 

 other species ; thus eggs of the eider-duck have been 

 found in the nest of a gull ; other similar cases are on 

 record, in some of which, from the species being 

 nearly allied, confusion might easily have arisen, 

 though at the time no doubt may have occurred in the 

 collector's mind. That it is easy to be mistaken is 

 shown by the slips made even by that great oologist, 

 Dr. T. M. Brewer, when at the lipight of his expe- 

 rience ; — for example, in publishing accounts of the 

 nidification of PJioenopepla nitens as that of Myia- 

 destes ^ownsendii^ and in one or two other instances 

 recorded occurring in his North American Oology. 



OVERCOMING DIFFICULTIES. 



It is not always easy to obtain the nest or eggs, in 

 good shape, even after you know where they are. 

 Sometimes, indeed, it is all but impossible, and at- 

 tended with great danger ; a consideration, however, 

 not likely toideter any ardent naturalist from attempt- 

 ing to enrich his collection. 



A large number of sea-birds, and many birds of 



