• Sterna tschegrava, Lepechin, N. Comm. Petrop. xiv. p. 500 (1769).

• Sterna caspia, Pallas, N. Comm. Petrop. xiv. p. 582 (1769).

• Sterna megarhynchos, Meyer and Wolf, Taschenb. deutsch. Vögelk. ii. p. 457 (1810).

• Thalasseus caspius, Boie, Isis, 1822, p. 563.

• Hydroprogne caspia, Kaup, Natürl. Syst. p. 91 (1829).

• Sylochelidon balthica, Brehm, Vög. Deutschl. p. 769 (1831).

• Sterna schillingii, Brehm, tom. cit. p. 770 (1831).

• Sylochelidon caspia, Brehm, tom. cit. p. 770 (1831).

• Helopus caspius, Wagler, Isis, 1832, p. 1224.

• Thalassites melanotis, Swains. B. of W. Afr. ii. p. 253 (1837).

• Sylochelidon strenuus, Gould, P. Z. S. 1846, p. 21.

• Sylochelidon melanotis, Bonap. C. R. xlii. p. 772 (1856).

• Sterna melanotis, Hartl. Orn. Westafr. p. 254 (1857).

• Sterna vulgaris, Ellman, Zool. 1861, p. 7472.

• Thalasseus imperator, Coues, Pr. Phil. Acad. 1862, p. 538.

Native name.—Tara-nui.

Ad. ptil. æstiv. suprà dilutè cinereus, uropygio et supracaudalibus albis: caudâ albâ: tectricibus alarum dorso concoloribus: remigibus extùs canescentibus, primariis versùs apicem saturatioribus, scapis albis, pennis minoribus et secundariis dorsalibus pallidè cinereis: pileo et nuchâ cristatä nigris: facie laterali a narium basi ductâ cum collo laterali et corpore subtùs toto albis: rostro lætè corallino, flavo vario, versùs apicem brunnescente, spice ipsâ corned: pedibus nigricanti-brunneis: iride nigrâ.

Ad. ptil. hiem. similis ptilosi æstivæ, sed pileo albo minutè nigro striolato.

Adult in summer. Forehead and upper part of the head, described by a line from the posterior edge of the nasal groove, on each side, passing immediately under the eyes, and meeting in an acuminate point below the occiput, satiny black; back, rump, and upper surface of wings and tail delicate silvery grey; primaries darker grey, with white shafts; the rest of the plumage pearly white. Irides black; bill beautiful coral-red, mixed with yellow, and shaded with brown near the tips of both mandibles, which are horn-coloured; legs and feet blackish brown. Length 22 inches; extent of wings 53; wing, from flexure, 16·25; tail 6·25 (middle feather 1·5 shorter); bill, along the ridge 2·6, along the edge of lower mandible 3·6; bare tibia ·5; tarsus 1·75; middle toe and claw 1·5.

Adult in winter. Differs in having the black plumage of the head largely spotted with white, especially on the forehead and lores.

Obs, At the breeding-season this bird has the plumage suffused with an extremely delicate roseate hue, which fades away after life is extinct, but does not wholly disappear from the preserved skin.

Young. Has the vertex and crown similar to the adult in winter, but the white preponderating, and the coronal cap extending halfway down the cheeks; the primaries are sooty grey, and the wing-coverts greyish brown with paler edges. Bill reddish brown.

page 74

Note. Dr. Elliott Coues, in his “Review of the Terns of North America” (Proc. Phil. Acad. l. c.), makes the following remarks on the synonymy of this species:—“The proper specific appellation of the Caspian Tern is not ‘caspia, Pallas,’ but ‘tschegrava, Lepechin,’ which latter name is proposed in the same work in which Pallas calls the bird ‘caspia,’ but has priority by several pages. As, however, the word is not only barbarous, but exceedingly cacophonous, and especially as caspia has become so well established by common consent, I do not think it would be expedient to supersede Pallas’s name in view of the very slight priority of that of Lepechin.”

The history of this fine Tern has already been so fully written that I deem it almost sufficient to record here that it occurs all round the New-Zealand coasts, where its habits are the same as in other parts of the globe. It inhabits the Palæarctic and the greater part of the Nearctic Regions, also the African, Indian, and Australian coasts. It is a rare summer visitant to the eastern and southern shores of England.

It is usually met with in pairs; but I have occasionally observed parties of five or more resting on the sands near the mouths of our tidal rivers. It subsists entirely on small fish, for which it plunges into the water with considerable force; and at certain seasons it is accustomed to follow the shoals of sprats far up the river-courses, where it may be seen hovering lightly over the water in pursuit of its finny prey, and occasionally alighting to rest on a jutting stump or projecting point of rock. I have seen one capture a small flounder, and kill it by battering before swallowing it. It often makes several feints at the water before dropping into it; but the bird never misses its aim, and on rising again with a fish usually takes a wide sweep on the wing whilst stowing it away in its capacious crop. I have observed that, on the wing, this species does not move its head to and fro in the manner of the smaller Terns, but carries it vertically, with its powerful beak pointing downwards. “When resting on the ground the apparently disproportionate head gives the bird an ungainly appearance; but this disappears the moment the wings are expanded; and the flight, which is generally performed in wide circles, may be described as very easy and graceful. It is less active, however, on the wing than the smaller Terns. Nevertheless it appears to have the most perfect self-control; for example, I observed one pursuing a direct flight up a river-course, at a high elevation, when it met another coming in the opposite direction at a lower level. Moved by some sudden impulse it abruptly and quickly wheeled right-about, dropped to the lower plane, and succeeded in overtaking the other bird. Writing of it, the Earl of Pembroke says: “The Tern, if the sea be smooth, has a neat little way of picking up small morsels from the surface, and, if necessary, makes a very respectable Gannet-like splash; never, however, as far as I have seen, immersing himself, and always keeping his wings in motion to get him up again.” Its ordinary cry is harsh and unmusical, consisting of a loud rasping note, not unlike the low cry of the domestic Goose; at other times it utters a long peevish squeal or whistling cry, fairly represented by the syllables queeâ-queeâ. When resting on the sands it is habitually silent, but always utters its guttural cry when preparing to take wing.

The breeding-season of this species extends from November to January. The young birds, however, follow their parents up to the end of March, settling down with them on the sands, quivering their wings as if impatient of attention, and making an incessant squealing or whining cry. The eggs, usually two in number, are deposited on the bare sand, a slight hollow in the surface meeting the requirements of a nesting-place. They are ovoido-conical in form, measuring 2·7 inches in length by 1·9 in breadth, and varying from creamy white to a delicate greenish-white tint, the whole surface marked with spots and blotches of dark brown, intermixed with pale splashes of purple, these markings being most numerous at the thicker end. It should be mentioned, however, that, as in the case of other Terns, the eggs present some variety both as to size and colour; there is a specimen in the Canterbury Museum (of a pale yellowish-brown tint, thickly marked and spotted with dark brown) which measures only 2·4 inches by 1·6.