Eggs.—The knot lays four eggs, perhaps sometimes only three. The eggs are ovate pyriform in shape, with a slight gloss. In the set of three eggs, taken by the Crockerland expedition and now in Col. John E. Thayer's collection, the ground colors vary from "pale olive buff" to "olive buff"; they are spotted all over, but more thickly at the larger end, with small spots or scrawls of "sepia," "Saccardo's umber," and "Vandyke brown," with underlying spots of "pallid" and "pale brownish drab."
The other set of four eggs, from the same source and now in the American Museum of Natural History, is thus described for me by Ludlow Griscom:
Ground color varying from white with the faintest tinge of light olive (1 egg) to "olive buff" (2 eggs) and deep "olive buff" (1 egg); clouded and spotted, especially at the larger end, with shades of color varying from "dark olive buff" to "olive brownish," the intensity varying in direct proportion to the intensity of the ground color; where the spots coalesce into blotches at the larger end of the darkest egg, the color is blackish brown; the spotting is scant at the smaller end.
Referring in his notes to the same two sets of eggs, Doctor Ekblaw describes the ground colors as varying from very light pea-green, almost gray, to dark pea-green, "with brown, umber, and almost black dots and blotches of varying size and shape over the green, and faint subcrustal lavender blotches showing through." Other eggs which I have seen figured or described would fit these descriptions fairly well. The measurements of 42 eggs average 43.1 by 29.6 millimeters; the eggs showing the four extremes measure 49.8 by 33.8, 39.9 by 29.7 and 41.5 by 27.7 millimeters.
Young.—The period of incubation is said to be between 20 and 25 days. Both sexes have been taken with incubation patches, so this duty is doubtless shared by both. I quote from Doctor Ekblaw's notes again:
Though we found but two clutches of eggs, we discovered many families of young birds. They are able to leave the nest as soon as hatched, little gray downy chicks with faint blotches of brown, so like the dried tufts of dryas as to be quite undiscoverable when hidden among them. Three or four, or rarely five, chicks constitute the group. Their faint plaintive "cheeps" are so ventriloquistic and illusory that it is impossible to distinguish the direction from which they come. When an intruder approaches the little fellows squat at the signal from the parent bird wherever they happen to be at the time, and remain immovable as the pebbles and tufts of dryas until the danger is over, even though it be hours before the safety seems assured. Even the tiniest of these downy fledglings seem able to look after themselves. They run eagerly and constantly about independently pursuing the moths, crane flies, and flies upon which they feed, often 40 or 50 feet from their mother. The first signal from the mother, a mellow, solicitous coo-ee transforms them into immovable pebbles or tufts of dryas. When they are discovered and realize that their concealment is no longer effective, they scatter panic stricken like a flock of little chickens, chirping appealingly to their "mother" who dashes valiantly to their defense, quite beside "herself" with concern, fear, and anger.
Whenever the jaegers, relentless brigands of birdland, appear, the old knots do not hesitate to attack. In combining their forces, they drive full into the bigger birds, striking them from beneath again and again, until they chase them away. The young grow fast. In three weeks after hatching they are almost full grown and half-clothed in feathers, quite capable of taking care of themselves. They stay until they leave among the interior plains and plateaus, coming down to shore only when they are able to fly—and then the southward migration begins at once.
Apparently, the knots, like the phalaropes, reverse part of their secondary sex characteristics, for all the birds caring for the young that I collected were males, beyond doubt. When I examined the first bird that I collected with its young, I was surprised to find that the supposed "mother," who had so valiantly and zealously shielded "her" little ones, was actually father. I thought then that perhaps the mother bird had been killed and that in the emergency the father had assumed the responsibility for the youngsters; but later I became convinced by examination of many birds, that invariably it is the male that cares for the fledglings after they are hatched. The female incubates the eggs, but the male relieves her of further care in bringing up the family.
Plumages.—In its natal down the young knot can be easily recognized by the grayish, mottled colors on the upper parts and the absence of browns and bright buffs. The shape of the bill, characteristic of the species, is also diagnostic. The crown, back, rump, wings, and thighs are finely mottled or spotted with black, white, gray and dull "cinnamon buff," the last being the basal color. The forehead, the sides of the head, the throat, and the entire under parts are dull white, tinged with grayish on the flanks and crissum. There is a broad median stripe on the forehead, a broad loral stripe from the bill to the eye and a narrower rictal stripe of black.