450 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
Vog., ii, 1891, 206—Suarre, Review Rec. Att. Classif. Birds, 1891, 72 
Hand-list, 1899, xiv, 188.—SaunpErs, Cat. Birds, Brit. Mus., xxv, 1896, 
xiii, 4, 152.—Bepparp, Struct. and Classif. Birds, 1898, 356.—Sa.vin and 
GopmaN, Biol. Centr.-Am., Aves, iii, 1903, 416.—Know tron, Birds of the 
World, 1909, 393. 
=Rhynchopide Ripeway, Proc: U. 8. Nat. Mus., vi, April 11, 1883, 409.— 
Barrp, Brewer, and Ringway, Water Birds N. Am., ii, 1884, 191. 
=Rhynchopside Ripeway, Proc. U. §. Nat. Mus., iii, Sept. 4, 1880, 240. 
=Rynchopide AmeRIcAN OrniTHoLOoGists’ Union, Check List, 1886, 96; 3rd ed., 
1910, 48.—OxsERHOLSER, Outl. Classif. N. Am. Birds, 1905, 3. 
Very long-winged, small-footed Lari with bill wholly unique, the 
mandible much longer than the maxilla, both compressed to knife-like 
thinness (except at extreme base), the distal portion of the maxilla 
grooved beneath to receive the very sharp tomia of the distal portion 
of the mandible, the latter much higher at tip than the latter and 
obliquely truncate or subtruncate in lateral profile. Wing very long, 
pointed, the longest primary exceeding distal secondaries by about 
two-thirds length of wing. Ambiens muscle and biceps slip absent 
(present in other Lari); tendons to ulna side of arm, 2 (1 or none in 
other Lari). 
The Rynchopide are perhaps most nearly allied to the Sternide 
but differ—not only from the latter but from all other birds—in the 
altogether peculiar conformation of the bill. They also differ from 
other Lari in absence of the ambiens muscle and biceps slip, and in 
possessing two tendons to the ulna side of the arm. 
In general habits the Rynchopide are much like the Sternide 
and Laride, but their manner of feeding is wholly different, for in 
search of their food the mouth is opened and the long, knife-like 
mandible buried in the water as the bird skims along its surface. 
Only one genus is known, this being represented by about four 
species, of which two are American, the others inhabiting the seas 
and estuaries of Africa and India, respectively. 
Genus RYNCHOPS Linnezus. 
Rynchops Linnamus, Syst. Nat., ed. 10, i, 1758, 188; ed. 12, 1, 1766, 228. (Type 
by monotypy, Rynchops nigra Linneus.) 
Rhynchops (emendation) Latuam, Index Orn., ii, 1790, 802. 
Rhijncops (emendation) Temmincx, Cat. Syst., 1807, 181. 
Rhincops (emendation) Bonaparte, Ann. Lyc. Nat. Hist. N. Y., ii, 1828, 19. 
351, 447. 
Rhyncops (emendation) Vizrttot, Nouv. Dict. d’Hist. Nat., iii, 1816, 338. 
Rygchopsalia Brisson, Orn., vi, 1760, 222 (ex Barrére, Orn. Sp. Nov., 1745. 20). 
(Type, ‘‘ Rygchopsalia” =Rynchops nigra Linneus.) 
Rhynchopsalia (emendation) GLocER, Hand-u. Hilfsb., 1842, 463. 
Psalidorhamphos « Dumont, Dict. Sci. Nat., iv, 1805, 173. (Substitute name for 
Rynchops Linneus.) 
4 VaNls (Wadidos), a pair of shears, a kind of razor; paudos, beak. (Richmond.) 
