556 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.43. 



Tyi^e-locality . — Valley of Mexico, State of Mexico, Mexico.^ 

 , GeograpMcal distribution. — Mexico, Central America, and northern 

 South America, breeding in the Upper Austral, Lower Austral, Upper 

 Tropical, and Lower Tropical zones: north to southern Sinaloa; 

 Colonia Garcia, northwestern Chihuahua; and Tamauiipas; south- 

 east through all of Mexico to Guatemala, Nicaragua, Costa Rica, 

 Panama, and Merida, Venezuela. Resident all the j^ear practically 

 throughout its range, except perhaps in South America. 



From Ardea herodias Jiyperonca the present subspecies may be 

 distinguished by its shorter wing, darker neck and upper parts ; from 

 Ardea lierodias herodias by longer wing and tail and darker neck and 

 upper surface. The young in first plumage are like those of Ardea 

 herodias fannini, but are somewhat lighter on neck and upper parts. 



A single adult from Chihuahua City, Chihuahua, Mexico (No. 

 187287, U.S.N.M.), taken February 22, 1904, incHnes very little 

 toward Ardea herodias treganzai; and a juvenal from Tamauiipas, 

 exact locality unknown (No. 30477, Acad. Nat. Sci. Phila.), appears 

 also to be A. h. lessonii. Specimens examined from Nicaragua and 

 Costa Rica are all in juvenal plumage, and without adults it is diffi- 

 cult to place them with certainty. They are no darker than juvenal 

 Ardea herodias herodias, and ixdght suggest the existence of another 

 race in this region, were it not that a juvenal of typical Ardea herodias 

 lessonii, from Patzcuaro, Michoacan, Mexico, is precisely the same in 

 color. It may be, therefore, that the young of Ardea herodias lessonii 

 is not darker than the same age of Ardea herodias herodias, although 

 the adult is decidedly so. At any rate, until more satisfactory ma- 

 terial is available, the bird of Central America do^^'^l to Costa Rica, 

 inclusive, must pass as Ardea herodias lessonii. 



A single bird in juvenal plumage from Empire, in the Canal Zone, 

 Panama, is practically identical -with young birds from Alexico, Nic- 

 aragua, and Costa Rica, except for being rather darker, more slaty, 

 on the neck. Another bird, from Panama is, however, darker above 

 than any adult specimen of Ardea herodias lessonii that we have 

 seen; and with, more material, the Panama bird may be separable 

 subspecificall}^ from that of Mexico. Since the above-mentioned 

 example is in rather an interesting phase of plumage, almost adult, 

 and very much more brownish than either 3'oung or adult normally 

 are, the following description may be of interest: 



Almost adult male, No. 230144, U.S.N.M., Biological Survey col- 

 lection; Fort Lorenzo, Panama, June 21, 1911; E. A. Goldman. 

 Forehead and sides of sinciput cloA'e brown; sides of crown, and 

 occipital crest, black; superciliary stripe pale gray; center of crown, 

 vertical crest, postocular region, malar region, chin and middle of 

 upper throat, white; subauricular region and sides of throat light 



» Thus here restricted for the sake of definiteness. 



