514 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



mandible browuish white or pale brownish buli' (in dried skins); legs 

 and feet horn color (in dried skins). 



Young. — Very different in coloration from adults; pileum and nape 

 plain slat}^ black; back and scapulars dusky, with larg-e more or less 

 guttate spots of brownish buff' or pale wood brown ; rump and upper 

 tail-coverts plain light ])uff3' grayish brown; lighter bands of wings 

 and tail brownish buff or pale wood brown instead of whitish; super- 

 ciliary stripe brownish buff, becoming ver}'^ narrow (sometimes obso- 

 lete) anteriorh"; throat, chest, and breast immaculate, the last two 

 strongly suffused with dull brownish buff"; dusk}^ bands on flanks and 

 under tail-coverts much less distinct than in adults. 



Adult male.— Length (skins), 181-193 (186.9); wings, 84-95 (91.5); 

 tail, 80-89 (85.5); exposed culmen, 19.5-25 (22.1); tarsus, 27-28.5 

 (27.4); middle toe, 16-19 (17.4). « 



Adultfemale.—Jjength (skins), 171-187 (179.5); wing, 83-89.5 (85.9); 

 tail, 77-84.5 (78.9); exposed culmen, 18-20 (18.7); tarsus, 26-27.5 

 (26.7); middle toe, 16-17.5 (16.4).^ 



Southwestern portion of Mexican plateau, in States of Morelos 

 (Huitzilac), Michoacan (Patamban), and Mexico (Rio Frio; Mount 

 Ixtaccihuatl; Ajusco; near City of Mexico). 



Campylorhynchas megaloplerns Lafresnaye, Rev. Zool., viii, 1845, 339 (Mexico; 



type now in coll. Boston Soc. Nat. Hist.; see Eidgway, Proc. Bost. Soc. 



Nat. Hist, xxiii, 1888, 385).c— Des Murs, Icon. Orn., 1845-i9, pi. 54.— 



Bonaparte, Consp. Av. i, 1850, 223. 

 (J[imipylorhynclius] megalopterus Gray, Gen. Birds, i, 1847, 159. 

 'ICampijlorhynehus'] megalopterus Gray , Hand-list, i, 1869, 192, no. 2639. 

 Heleodytes alticolus Nelson, Auk, xiv, Jan., 1897, 68 (Huitzilac, Morelos; coll. 



U. S. Nat. Mus.). 



HELEODYTES NELSONI Ridgway. 

 GRAY CACTUS WREN. 



Similar to JI. megalopterm., but smaller, paler, and browner, with 

 spots on breast, etc., grayish brown instead of blackish. 



Adults {sexes alike). — Pileum light grayish brown (broccoli ])rown 



" Nine specimens. 



& Eight specimens. 



<■ At the time when I examined Lafresnaye's types of this species no other speci- 

 mens were extant, and the series of the allied form {H. nelsoni) was then too small 

 for satisfactory comparison. My conclusion that Lafresnaye's bird and that called 

 C. megalopterus by Dr. Sclater and others (later erroneously identified by Professor 

 Baird with C. pallescens Lafresnaye) represented the same species proves, in the light 

 of additional material, to have been a mistake. Mr. Nelson, recognizing the dis- 

 tinctness of the two forms, and accepting my identification of C. megalopterus with 

 the paler bird of the eastern side of the plateau, was thus unfortunately led to 

 describe the wrong bird as new, his Heleodytes alticolus and Lafresnaye's Campylo- 

 rhyncMis megalopterus unquestionably being the same form. 



