diameter of the cavity is one and seven-eighths, its depth one and one-half inches. From these measure- 

 ments it will be seen that the wall of the nest is very thin. 



A nest taken June 20th, 1882, is similar as regards position, but is a little larger externally, and 

 has mixed with the flaxen fibres of the foundation and superstructure strips of grape-vine bark, and with 

 the hairs of the lining split grass and roller-grass. Another nest discovered June 24th, 1883, in dense 

 upland woods, was situated twelve feet from the ground on a slightly inclined hickory sapling, at a 

 point where a small twig branched from the main trunk at an angle of about 45°. It is constructed so 

 that the twig runs through it, between the lining and the superstructure. Upon one side about two- 

 thirds of the nest is exterior to the crotch. Its foundation and superstructure are composed of flaxen 

 fibres, inner bark of grape-vine in long shreds, and balls and strings of snow-white web from a peculiar 

 plant-louse which infested the maples the past year. The grape-vine bark is most abundant around the 

 rim. The lining is composed of very finely split grasses, long black horse-hairs, and one black feather. 

 The materials are not wound around the trunk, but arc fastened to the bark by web. The external 

 diameter of the nest is about two and one-half inches; the external depth two and three-eighths. The 

 diameter of the cavity is one and seven-eighths; the depth one and one-half inches. This nest, although 

 much more loosely built, and some larger externally than the others, has exactly the same internal di- 

 mensions. Other materials besides those mentioned in the above descriptions, often enter into the com- 

 position of the nest; such as soft vegetable-downs, rootlets, and leaves. Some nests are composed largely 

 of down and fibres felted together, and some are lined entirely with split grasses or rootlets. But what- 

 ever the materials or external dimensions, the diameter of the cavity is very uniform. 



EGGS: 



Four or five eggs constitute a set, four is the usual number. Those in my collection from Ohio, 

 vary in long-diameter from .59 to .68, and in short-diameter from .45 to .51. Ten eggs, from as many 

 sets, collected in widely different parts of the United States, come nearly within the same limits. The 

 usual size is about .49 x .60. A set of four measures, respectively, .48 x .61, .50 x .62, .49 x .60, and .48 x 

 .60. The ground-color of the shell is white, often of yellowish or soiled appearance. The markings are 

 yellowish-brown of quite uniform tint, but of slightly various shades. The deep shell-marks are slate 

 color. An egg of the usual pattern is blotched, clotted, and speckled; the clots and speckles are scattered 

 sparingly over the whole shell, and about the crown the blotches, which are in places confluent, form a well- 

 marked wreath. An extreme specimen has its pointed half immaculate, but about the base there is a 

 well-defined ring of small blotches, dots, and speckles, rarely confluent, of pale surface marks and deep 

 shell-marks in about equal proportions, and besides several fine, irregular lines. Another extreme speci- 

 men is boldly blotched, clotted, and speckled, from point to base, most plentifully at the base, with a 

 dark shade of yellowish-brown. Between these extremes there are various combinations. 



DIFFERENTIAL POINTS: 



The nest and eggs of the Redstart have often been said to resemble those of the Summer Warbler, 

 and there is. on casual inspection quite a similarity. Reference to page 71 will, however, show quite dis- 

 tinct points of difference between the nests, not only as to size, but also as to materials, and mode of 

 construction. The eggs of the two species are at times very much alike, but as a rule those of the Red- 

 start are the smaller. See also table. 



REMARKS : 



The illustration, Plate LI, represents a nest of the American Redstart, collected June 24th, 1883, 

 a description of which is given above. The eggs figured show the sizes, shapes, and patterns of mark- 

 ings ordinarily observed, the middle one being perhaps the commonest form. 



182 



