The Female is similar to the male, but somewhat smaller.
Young in winter. Plate CCCXVIII. Fig. 2.
The young in winter is similar to the adult, but with the head and neck white, the dark colours of a browner tint.
Length to end of tail 18 inches, to end of wings 18 1/2; extent of wings 30 1/2. Weight 13 oz.
In structure the Avosets are similar to the Numenii and Totani. In an adult female the tongue is very short in proportion to the length of the bill, being only 1 3/4 inch long, slightly emarginate at the base with a few conical papillæ, slender, tapering to a point, horny on the back, and flattened above. On the palate are two longitudinal series of blunt papillæ. The posterior aperture of the nares is linear, 10 twelfths long, papillate on the edges. The œsophagus is 7 inches and 9 twelfths long, inclines to the right side, and when the neck is bent becomes posterior at the middle, as in the Herons and other long-necked birds; its diameter 5 twelfths at the upper part, dilated to 8 twelfths previous to its entrance into the thorax. The proventriculus is 1 inch long and 7 twelfths in diameter; its glandules cylindrical, 1 twelfth long. The stomach is a gizzard of moderate strength, oblong, 1 1/2 inch in length, 10 twelfths in breadth, its right lateral muscle 4 twelfths thick. Its contents were remains of small shells. Its inner membrane of moderate thickness, hard, longitudinally rugous, and deeply tinged with red. The intestine is 3 feet long, and 4 twelfths in diameter; the rectum 2 inches long; of the cœca one is 2 3/4 inches long, the other 2 1/4, their diameter 2 twelfths.
In another individual the intestine is 3 feet 9 inches long; one of the cœca 2 3/4 inches, the other 3; the stomach 1 1/2 by 1 1/12. Its contents small shell-fish and fragments of quartz.
The trachea is 6 1/2 inches long; its rings extremely thin and unossified, 140 in number, its diameter 3 1/4 twelfths, nearly uniform throughout, but rather narrower in the middle. The lateral muscles are very thin. The bronchi are short, of about 10 rings.
LEAST TERN.
Sterna minuta, Linn.
PLATE CCCXIX. Adult and Young.
Sylph-like bird of the waters, how delightful has it been to me to gaze on thy gliding movements, on the fannings of thy gentle wings, on the delicate silvery glance of thy soft and sattiny bosom, as thou camest from distant and unknown shores, when the winter had passed away, and the mild breezes of early summer blew around thee, and thou soughtest a place of safety in which to sojourn for a time. That frail frame of thine must have suffered many a hardship. Fronting that last damp and chilling blast, I have seen thee gathering up all thy little strength to force thy way; and when the fury of the tempest assailed thee, wert thou not glad to seek for refuge under yon bold headland! Ah, deny it not, for I have seen the delight expressed by thee, when after awhile, returning calm and sunshine revived thee, and thou spreadest thy wings anew, to ramble gaily over the still turbulent waters. Well knowest thou, heaven-taught, each bar and shallow along the desolate shore which thou skirtest pilotless; soon shalt thou reach the haven where last summer smiled on thee and thy brood; and there shalt thou gracefully alight by the side of one whose love is all to thee.