544 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



Adult male.— Length (skins), 285-306 (296); wing, 165.5-175 (171);. 

 tail, 158-169.5 (163.7); exposed culmen, 12.5-15 (13.5); tarsus, 

 25-28.5 (26.7); middle toe, 20.5-22.5 (21.3).» 



Adult female.— Length, (skins), 248-271 (257); wing, 159.5-164 

 (162.1); tail, 135-150 (144.5); exposed culmen, 11-14 (12.2); tarsus, 

 23.5-26.5 (24.7); middle toe, 18-20.5 (19.3).* 



Southeastern Mexico, in States of Vera Cruz (Rivera; Orizaba; 

 Mirad6r; 75 miles southwest of Tampico; Omealca; Cordova?;" 

 Jalapa?;" Misantla?;" Co^tepec?;" Huatusco?;" Rio Rancho 

 Nuevo?;" Santa Ana?; ■= Playa Vicente ? ") and Tabasco (Frontera, 

 March; Teapa, March) ; southern Tamaulipas (Tampico)?;" Puebla 

 (Tehuacdn; Mazatiop&m) ?." 



{1)Nyctidromus americanus (not Caprimulgus amerimnus Linnseus) Sclater, Proc. 



Zool. Soc. Lond., 1856, 285 (Cordova, Vera Cruz; crit); 1859, 367 (Jalapa, 



Vera Cruz). 

 (?)Nyctidrcmms ammcamisl Sclater and SaiiVdt, Ibis, 1859, 125, part (Mexico; 



crit.). 

 {7)N[yctidrormts] americanus Oabanis and Heine, Mus. Hein., iii, 1860, 92, part 



{'!)Nyctidromus albicoUis (not Caprimulgus albicoUis Gmelin) Sclateh, Proc. Zool. 

 Soc. Lond., 1866, 144, part (monogr.; s. Mexico). — ^Fekrari-Pekez, Proc. 

 U. S. Nat. Mus., ix, 1886, 158 (Tehuacan, Puebla). — Haetert, Cat. Birds 

 Brit. Mus., xvi, 1892, 587, part (Tampico?, Misantla, Jalapa, Orizaba, Playa 

 Vicente, and Teapa, Mexico). — Salvin and Godman, Biol. Centr.-Am., ii, 

 1894, 393, part (Misantla, Jalapa, Coatepec, Huatusco, Rio Rancho Nuevo, 

 Santa Ana, Orizaba, Cordova, and Playa Vicente, Vera Cruz; Mazatiopam, 

 Puebla; Tampico, s. Tamaulipas; Teapa, Tabasco). 



{?)Nyctidromus albicoUis merrilli (not of Sennett?) Chapman, Bull. Am. Mus. 

 N. H., X, 1898, 34 (Jalapa). 



{'i)N]i)ctidromus\ albicoUis {typicm) Hartbrt, Tierreicli, Podaig., Caprim. 

 Macropt., 1897, 32, part (Mexico). 



Nyctidromus albicoUis sumichrasti Ridgwat, Proc. Biol. Soc. Wash., xxv. May 4, 

 1912, 91 (Frontera, <* Tabasco, s. Mexico; coll. U. S. Nat. Mus.). 



NYCTIDROMUS ALBICOLLIS NELSOWI Ridgway. 



HELSOK'S CUl£jO. 



Decidedly larger than N. a. albicoUis, with grayish phase much 

 paler and tawny phase averaging lighter and brighter, with buff 

 markings of upper parts broader; gray phase similar in coloration to 

 that of N. a. merrilli, but size much less. 



o Three specimens. 



5 Five specimens. 



Not having seen specimens from these localities I can not be sure that they 

 represent the present form. Some of them, at least, doubtless do; but others may be 

 N. a. merrilli, ■which in winter extends its range southward to Vera Cruz and Puebla. 



"J By error, the type locality was given in the original description as Teapa instead 

 of Frontera. 



