Order ANSERES.] [Fam. LARID^E. 



STEKNA CASPIA. 



(CASPIAN TERN.) 



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



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



Sterna megarliynclios, Meyer and Wolf, Taschenb. deutsch. Vogelk. ii. p. 457 (1810). 



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



Hydroprogne caspia, Kaup, Natiirl. Syst. p. 91 (1829). 



Syloclielidon balthica, Brehm, Vog. Deutschl. p. 769 (1831). 



Sterna scMllingii, Brehm, torn. cit. p. 770 (1831). 



Syloclielidon caspia, Brehm, torn. cit. p. 770 (1831). 



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



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



Syloclielidon strenuus, Gould, P. Z. S. 1846, p. 21. 



Syloclielidon melanotis, Bonap. C. B. xlii. p. 772 (1856). 



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



Sterna vulgaris, Ellrnan, Zool. 1861, p. 7472. 



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



Native name. — Tara-nui. 



Ad. ptil. astiv. supra dilute cinereus, uropygio et supracaudalibus albis : cauda alba : tectricibus alarum dorso 

 concoloribus : remigibus extus canescentibus, primariis versus apicem saturatioribus, scapis albis, pennis 

 miuoribus et secundariis dorsalibus pallide cinereis : pileo et nucha cristata nigris : facie laterali a 

 narium basi ducta cum collo laterali et corpore subtus toto albis : rostro laete corallino, flavo vario, 

 versus apicem brunnescente, apice ipsa cornea : pedibus nigricanti-brunneis : iride nigra. 



Ad. ptil. Mem. similis ptilosi asstivse, sed pileo albo minute 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-fed, mixed with yellow, shaded with brown near the tips of both mandibles, which are 

 horn-coloured ; legs and feet blackish browri. 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 l - 75 ; middle toe and claw l - 5. 



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

 the forehead and lores. 



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