Darters cannot be classed as marine birds, though they frequent inlets of the sea as well as lakes and rivers, where they sun themselves with outspread wings on some stump, rock, tree, or even tuft of rushes, while seldom admitting of a near approach. When disturbed, they circle in the air with the neck drawn back upon the shoulders, as do the Pelicans; but the flight is laboured, and they are much more at their ease in water, where they swim very low, exposing only the head and neck, or even the bill, if danger threatens, and having a very snake-like appearance, as they {81}sway gracefully from side to side in their endeavours to keep the intruder in view. Hardly a ripple follows the prolonged dive, while below the surface the wings are but slightly used, the tail being often expanded, and the feet acting as powerful paddles. On reappearance a fish is generally to be seen grasped in the bill or transfixed by it, the peculiar mechanism of the vertebrae of the neck allowing the head to be darted forward at a moment's notice for the capture;[83] subsequently the prey is jerked up into the air, cleverly caught and swallowed. The food, which seldom varies, is sometimes obtained by the bird standing with the body immersed to waylay the passing shoals; but if Gould is correct in adding frogs, newts, and aquatic insects to the diet, these must be procured very differently. The nest, generally situated over water, is a flat or concave fabric of sticks, lined as a rule with leaves, moss, or roots, and often used for several years in succession. High trees or bushes are indifferently chosen, and colonies are usually, but not invariably, formed, several pairs being accustomed to breed in proximity on the branches. The two to five eggs are greenish-blue with chalky incrustation, like those of Cormorants, though smaller and more delicate. The note is short and hoarse. Both sexes are said to incubate, and to regurgitate food for the young.[84] Jerdon says that the scapulars of the Indian Darter were royal badges among the Khasias. It is tamed by boatmen in Bengal. Fam. IV. FREGATIDAE.–_Fregata aquila_, the Frigate- or Man-of-War-Bird, the latter of which names is sometimes transferred to the Albatroses and smaller Skuas, is met with throughout the tropical regions, and has even strayed as far north as Nova Scotia. It is blackish-brown with green and purple reflexions; the bill is bluish, the feet are black, the orbits, lores, and pouch–inflated in flight–scarlet. The female is browner above and white below, with pinkish feet and no perceptible pouch; while the young resemble her, but shew some white on the head and neck. _F. minor_, found from Madagascar to Papuasia and North Australia, but seldom beyond these limits, is smaller, with less purple gloss and a white mark on each flank. {82}[Illustration: FIG. 24.–Frigate Bird. _Fregata aquila._ × ⅛.]