194 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



AMBLYCERCUS HOLOSERICEUS (Lichtenstein). 

 PEEVOST'S CACiaiTE. 



Admit male. — Entirely black, most intense anteriorly, duller, and 

 usually more or less tinged with slate color, on rump, tail-coverts, and 

 posterior under parts; bill light olive-yellowish (pale yellowish green 

 to pale sulphur yellow in life), sometimes partly dusky in dried skins; 

 iris white or light yellow; legs and feet dusky horn color in dried 

 skins, plumbeous in life; length (skins), 200.7-264.2 (225); wing, 

 93.5-109.2 (101.6); tail, 91.4-114.3 (100.3); culmen, 28.5-33.3 (31); 

 depth of bill at base, 13.6-17.5 (16); tarsus, 31.8-35.6 (33); middle toe, 

 19.1-23.4 (21.3).' 



Adult female. — Similar to the adult male, but decidedly smaller and 

 the black rather duller; length (skins), 190.5-233.7 (206.8); wing, 

 82.6-97(91.9); tail, 88.9-101.6 (93.2); culmen, 27.9-31.8 (30); depth of 

 bill at base, 12.7-14 (13.2); tarsus, 20.2-31.8 (30.7); middle toe, 19.8- 

 21.1 (20.3).' 



Southeastern Mexico, in States of Tamaulipas (Alta Mira), Vera Cruz 

 (hot and temperate zones), Puebla (Metlaltoyuca), Mexico (Valley of 

 Mexico), Oaxaca (Teotalcingo, Playa Vicente, Santa Efigenia, etc.), 

 Chiapas (Guichicovi, Huehuetan), and Yucatan, through Central 

 America to Colombia, Venezuela, and western Ecuador (Babahoyo, 

 Guayaquil, Foreste del Rio Peripa, etc.). 



Stumus holosericeus Lichtenstein, Preis-Verz. Mex. Vog., 1831, 1 (Mexico); 



Journ. fiir Orn., 1863, 55 (reprint). 

 Caeicus holosericeus Salvin, Cat. Strickland Coll., 1882, 262 (Guatemala). 



' Eighteen specimens. 



^ Seven specimens. 



There is a remarkable range of individual variation of dimensions in this species, 

 and some variation with locality, but the series is not nearly large enough to show 

 whether the latter is important or not. Averages of the specimens examined are as 

 follows: 



Locality. 



Wing. 



Culmen. 



Depth 

 otbill 

 at base. 



Middle 

 toe. 



MALES. 



Four males from Vera Cruz and Puebla, Mexico. . 



Three males from Yucatan _ 



Three males from Guatemala 



Five males from Nicaragua and Costa Rica 



Two males from Veragua and Panama 



One male from Guayaquil, western Ecuador 



FEMALES. 



Two females from Vera Cruz 



Two females from Chiapas and Guatemala 



Two females from Nicaragua 



One female from Guayaquil 



101.1 

 107.4 



98.3 

 102.6 



97.8 



97 



93 

 94.2 

 92.7 

 82.6 



103.6 

 107.7 

 99.1 

 94.2 

 97.8 

 99.6 



98.3 

 94.2 



27.9 



15.2 



16 



13.5 



15.5 



16 



14.7 



13 

 14 

 13.2 

 12.7 



32.8 

 32.5 



31 

 31 



30.2 

 29.2 



21.3 

 20.6 

 20.6 

 22.1 

 22.1 

 21.6 



20.3 

 20.3 

 19.8 



