672 MR. H. SAUNDERS ON THE STERNIN.E. [Julie 20. 



to this species, I was for some time in doubt, until I observed 

 depicted in his plate a characteristic which distinguishes this species 

 from all other members of the group, viz. that the second tail-feather 

 is distinctly the longest on each side, whereas in other- Noddies 

 the third is the longest, the fourth being often but a trifle shorter. 

 In this arrangement of the tail-feathers Anous cteruleus comes next 

 to Gygis, and indeed is only placed here for convenience of treatment. 

 In its range it is probably the most restricted of the family, being 

 only found on the N.E. coast of Australia and throughout the coral 

 formations of the Pacific as far as Christmas Island, a little to the 

 north of the Equator. It was found breeding at Honden Island, in 

 the Paumotu group, on August 21st, depositing a single egg in the 

 concavities of the coral rock (Peale and Cassin) ; and we are told 

 that it does not wander far from coral islands. 



It is unnecessary in this paper to take notice of mere names, given 

 by Bonaparte and others, to which no description is attached ; but 

 there are two supposed species which were unknown to Messrs. 

 Sclater and Salvin when writing the " List of Neotropical Laridse," and 

 upon which the subsequent five years have thrown no light. In hope 

 of clearing up the subject, I give the names and a brief description : — 



Sterna atrofasciata, described by Philippi and Landbeck in 

 'Wiegmann's Archiv,' 1863, pt. i. p. 202, is an immature example 

 of a small species, the wing being 9 inches long, the bill 1 inch long, 

 black, red at the gape, the tarsus 7 lines, dull red, the mantle and 

 wings dark ash-grey, and the underparts and rump white. This 

 description does not apply to any known species ; and it may prove 

 to be a good one. The solitary specimen was shot at Llico, Col- 

 chagua, Chili, in December 1861, near the outlet of the great salt 

 lake of Vichuquen. 



S. acutirostris, Tsch. F. Peru. Aves, p. 305 (1846), is described 

 as 10 inches long, bill nearly 2 inches, wing 6*6, tars. "75; pure 

 white below, pale grey above ; bill black, with a red band in the 

 middle, and tip horn-colour. It is found in the lakes of the Cor- 

 dilleras, where Larus serranus breeds. A Tern with a bill nearly 

 a third as long as the wing is certainly remarkable ; but as, in de- 

 scribing S. exilis, Tschudi states that the total length is 7 inches, 

 and the wing alone 7 inches 3 lines (!), his measurements are some- 

 what incomprehensible, and it is advisable to wait further in- 

 formation. 



In concluding this revision I wish to acknowledge the assistance 

 that I have at all times received in the Zoological Department of 

 the British Museum, the Leyden Museum, from Prof. Peters of 

 Berlin, M. Bouvier of Paris, and also from many friends who have 

 placed their collections at my disposal. My thanks are especially due 

 to Mr. Osbert Salvin, whose fine series of American Sterninse has 

 always been available, and whose practical experience has, at times, 

 been of great assistance in intricate questions of synonymy and 

 doubtful nomenclature. 

 [36] 



