16 



All of these eggs are below the average size, several being 

 runts — one quite small. The measurements of the smallest egg 

 of each complete set is given in italics to readily illustrate the 

 status of laying. Thus it will be seen that the smallest egg of 

 the whole series was the commencement of the third set and the 

 next smallest size was the ending of the fifth set ("Descriptions 

 of Sets," No. 93). The largest egg was the fifth one laid, and 

 the next largest was the ninth — this one following the smallest 

 specimen. It is also of interest to observe that the eighteenth 

 and nineteenth eggs are larger than the first, second and third 

 ones laid. 



Fertility of Contents.— Close observations on this subject 

 seem to have been overlooked by many of the oologists who 

 contribute material for this booklet. Many observers seemed 

 content to let the matter of incubation rest as "fresh" if the nor- 

 mal eg.cs so proved, or "slight" if that stage prevailed. Id this 

 respect, much information which would otherwise have proved 

 invaluable in the preparation of this paper has been lost trace 

 of in the passing of the eggs from the nest to the cabinet. How- 

 ever a careful perusal of "Descriptions of Sets" will show that 

 much valuable data on the subject, has been taken, from which 

 a conclusion must be reached that while a majority of abnormal- 

 ities — except those abnormal in coloration only — are infertile, 

 many others are fertilized and incubation progressing. Gener- 

 ally the smaller runts contained no yolk; but in most of those 

 personally examined by myself, where this proved true, a small 

 streak of yellowish substance existed. Those abnormally color- 

 ed eggs which were typical in all other outward appearances, 

 were found to possess healthy contents— fresh ones had fertiliz- 

 ed yolks, and incubated ones had vigorous embryos— with but 

 few exceptions, and these were of no more frequent occurrence 

 than found among sets of normal eggs. 



Peculiarities of Shell. — A careful study of shell textu re 

 discloses a number of departures from the normal types. Re- 

 marks on these peculiarities are given under their respective set 

 numbers in "Descriptions of Sets" and need but little additional 

 touch here. It is worth while to note that thick and thin shell- 

 ed runts occur in about equal proportions, while monstrocities 

 seem to possess a shell of normal thickness, 'though sometimes 

 a very frail one is seen. 



Crevices and thin porous patches and streaks are seen in 

 the shells of some, and sharp, burr-like points and thick warty 

 surfaces are also noticed. One set exhibiting the latter pecu- 

 liarity is given a separate place in "Descriptions of Sets" under 

 the head of "Shell Texture." This, a set of Yellow-breasted 

 Chat (Icteria virens), was normal in all other particulars. 



