the sets of three contained an egg of the Cowbird (Molothrus 

 ater), so that these small sets were undoubtedly incomplete. 

 One set each of four and five eggs contained ay egg of the 

 Cowbird. 



More nests contained four than five eggs, and this number 

 is therefore the prevailing complement. 



Four nests contained 3 eggs each. 



Nine nests contained 4 eggs each. 



Five nests contained 5 eggs each. 



One nest contained 6 eggs. 



One nest contained 2 | eggs. (This one undoubtedly in- 

 complete, — Xest also contained a Cowbird's egg). 



In the sets containing the Cowbird's eggs, incubation was 

 progressing from slight to advanced in all but the set of five 

 winch was fresh. 



I he interference of the Cowbird is the cause of small sets 

 being found, and certainly the cause of one of the eggs in the 

 set of five being dented, and of an occasional egg of the War- 

 bler being found on the ground outside the nest. 



At the beginning of the second day after the completion 

 of the set incubation begins to blood-tinge the eggs, and on the 

 fourth da) the flesh of the embryos begins to form and in ten 

 days the young are hatched out. 



Fresh eggs, as they lie in the nest, are very beautiful in- 

 deed, exhibiting a fine, rich, cream-buff color, which is in- 

 tensified by the yolk. As incubation progresses, the egg shell 

 whitens in appearance until it is snow-white at the time incuba- 

 tion is about one-half complete. After this stage is reached, 

 the shell appears very glossy and turns a leaden hue. which 

 deepens until the young bursts it into fragments. 



Very few eggs hatch before June 1, but on May 28, 1899. 

 I found a nest containing four ytmng, two of which fluttered 

 out when I placed my hand near them. These youngsters 

 must have hatched on or about the 19th, and the laying com- 

 pleted on the (jth or loth, which is four days earlier than my 



