BIRDS OF NORTH AND MIDDLE AMERICA. 641 



X[ema] atricilla Cabanis, in Schomburgk's Reis. Brit. Guiana, iii, 1848, 761. 

 Larus ridibundtcs (not of Linnaeus) Wilson, Am. Orn., ix, 1814, 89, pi. 74, fig. 4. — 



Bonaparte, Ann. Lye. N. Y., ii, 1828, 358, footnote. — Leotaud, Ois. Trini- 

 dad, 1866, 532. 

 L[arus] ridibundus Bonaparte, Obs. Nom. Wilson's Am. Orn., 1826, [213J. 

 Larus plumbiceps (not of Temminck) Brehm, Lehrb., 1824, 722, part. 

 Xema wilsonii Boie, Isis, 1828, 358 (St. Croix, Greater Antilles). 

 Larus atricapillus [lapsus?] Abbott, Proc. Bost. Soc. N. II., i, 1842, 61. 

 [Atricilla] viacroptera Bonaparte, Naumannia, 1854, 212 (South America; nomen 



nudum). 

 [Atricilla] minor Bonaparte, Naumannia, 1854, 212 (Antilles; nomen nudum). 

 [Atricilla] cates6aei Bonaparte, Naumannia, 1854, 212 (w. North America; nomen 



nudum); Compt. Rend., xlii, 1856, 771. 

 Atricilla catesbsei Loche, Expl. Sci. Alger., Ois., ii, 1867, 189. 

 [Atricilla] catesbyi Bruch, Journ. fur Orn., 1855, 287 ("Warmere Nordamerika").— 



Heine and Reichenow, Nom. Mus. Hein. Orn., 1890, 359. 

 [Larus (Atricilla)] megalopterus Bruch, Journ. fiir Orn., 1855, 287 (Peru; Mexico). 

 Larus atricilla megalopterus Noble. Bull. Miia. Comp. Zool., Ix, Aug.. 1916, 367 



in text (coast U. S.; crit.). 

 [Larus {Atricilla)] microptents Bruch, Tourn. fiir Orn., 1855, 288 (s. parts of North 



America). 



CHROICOCEPHALUS FRANKLINH (Swainson and Richardson). 



FRANKLIN'S GULL. 



Adults in summer (sexes alike).— Head and upper portion of neck 

 plain slate-blackish or dusky purplish gray, more slaty anteriorly; 

 an elongated white spot on each eyelid; lower neck (aU round), 

 entire under parts, lower runip, and upper tail-coverts immaculate 

 white, the neck and inider parts more or less deeply suffused with 

 eosme pmk, especially in living or recently killed specimens; back, 

 scapulars, wings, and upper part of rump uuiform neutral gray, the 

 tertials and secondaries broadly tipped with white; five outer pri- 

 maries with a subterminal space of black, varymg in extent from 

 about 50 mm. on the second (from outside) to about 12.5 mm. on the 

 fifth, and tipped with white, these white tips varying in extent from 

 about 38 mm. on the outermost to less than 12 mm. on the rest, the 

 gray of basal portion on aU becoming white or nearly so distally, 

 next to the black subterminal area, the shafts white except within 

 the latter; remaining (proximal) primaries lighter gray, broadly, 

 but not abruptly, tipped with white, the sixth (from outside) some- 

 times with a subterminal bar or spot of black; tail white, the four to 

 six middle rectrices tinged with pale gray, especially the middle 

 pair; biU deep red with a more or less distinct subtermmal band of 

 darker red; iris dark brown; naked orbital ring, legs, and feet, deep 

 red. 



Adults in winter. — Similar to summer adults but head and whole 

 neck white, the occipital, auricular, and orbital regions dusky grayish; 

 bill and feet darker red, the former tipped with orange-reddish. 

 40017— 19— Bull. 50, pt 8 i2 



