The eggs of the pectoral sandpiper are of particular interest because they are perhaps the most beautiful of the many handsome shore-bird eggs that are found in the Hooper Bay region. Their rich and contrasting colors, their bold splashed markings, and high luster make them veritable gems of oological perfection. In all nests that came under our observation four eggs constituted the complement, and these generally nestled points together amid the crisp leafy lining of their birthplace, standing most often at an obtuse angle to the horizontal. In outline they range from subpyriform to ovate pyriform. The exterior of the shell has a smooth, almost polished surface that reflects in many eggs a high luster. The ground color varies considerably from dull white to "cream buff" and even to "deep olive buff," but in all sets I have seen the ground color and markings follow the same shades and types in the same set of eggs. The surface markings are bold and individual, and appear as if they were daubed with a paint brush. These large rich spots are elongated and are placed parallel to the long axis of the egg, showing but little tendency to spiral. The heaviest markings are at the larger end, often merging into a large "chocolate" blotch, and in one case this rich blot of color covered more than a fourth of the egg. The color of the markings ranges from "walnut brown" and "sepia" to "chocolate" and "blackish brown," with "chocolate" the predominating shade. The underlying spots are prominent and numerous on some eggs, while on others they are almost wanting. They vary from "pearl gray" to "violet gray," with an occasional egg inclined to "Isabella color." In fact, each different clutch of eggs exhibits some individual interesting peculiarity. My only set, taken for me by Mr. Hersey, would fit the above description very well, but it is not particularly handsome. The ground color is dull white or "pale olive buff," which is more or less evenly marked with small blotches and spots of "bister" and "bone brown." Mr. Murdoch (1885) says that they "may be distinguished from those of the buff-breasted sandpiper, which they closely resemble, by their warmer color." The measurements of 116 eggs, in the United States National Museum and in Mr. Brandt's collection, average 36.5 by 25 millimeters; the eggs showing the four extremes measure =38.5= by 25, 38 by =27=, =34= by 24.9, and 35.5 by =24.5= millimeters. _Young._--Mr. Conover writes to me as follows: