ARDEID^E — THE HERONS — ARDETTA. 



73 



tips of primary-coverts, secondaries, and inner primaries, rich cinnamon-rufous ; large area, cov- 

 ering middle -vving-covert region, pale ochraceous, or buff ; remiges and primary-coverts blackish 

 slate, except at tips. " Bill dark olive-brown above, edges of upper mandible and bare frontal 

 space yellow ; lower mandible pale yellow, inclining to flesh-color ; iris yellow ; feet dull greenish 

 yellow ; claws brown" (Audubon). Adult female : Similar to the adult male, but the greenish 

 black replaced by brown (varying from umber-drab to cinnamon, the pileum darker and usually 



Adult male. 



opaque blackish dusky) ; the buff stripe along outer Ijorder of scapulars much broader and more 

 conspicuous, and the stripes on the foreneck (usually but not always) more distinct. Otherwise 

 exactly like the male. Young : Similar to the adult female, but the feathers of the back and 

 scapular region tipped with buff ; the stripes on the foreneck also (usually) more distinct. 



Length, about 12.00-13.50 ; expanse, 17.00-18.00. Weight, about 4| ounces (Audubon). 

 Wing, 4.30-5.25 ; tail, 1.60-2.10 ; culmen, 1.60-1.90 ; de^ith of bill, .28-.35 ; tarsus, 1.50-1.75 ; 

 middle toe, 1.40-1.60 ; bare portion of tibia, .45-.50.1 



With a considerable series of specimens belbre us, we can observe no geographical variations 

 other than the slightly smaller size of skins froni Demerara and Tehuantepec. As to colors, no 

 tropical examples are brighter than two males from the eastern United States (1549, Carlisle, Pa., 

 and 1090, District of Columbia). The range of individual variation in color is also very slight, 

 though very great as to dimensions. 



In a considerable series of Least Bitterns from Guatemala, kindly submitted to us for exam- 

 ination Ijy ^Iv. Osbeit Salvin, there is a single specimen, which, while agreeing very closely in 

 plumage witli the adult male of the common North American species, is so different in propor- 

 tions as to leave little doubt of its specific distinctness. The tarsi and toes are disproportionately 

 shorter than in A. exilis, the former measuring only 1.15 and the middle toe 1.12, while the inner 

 toe is just perceptibly longer than the outer, measuring 0.98 against 0.95. The tibioe are com- 

 pletely feathered, even more so than in A. involucris. The other specimens, chiefly from the Lake 

 of Duenas, are all typical A. exilis, mostly young of the year, evidently reared in the locality. 

 W^ithout venturing to name this bird, we give below a full description.- 



1 Extremes of twenty-one adult examples. 



2 Char. Similar to A. exilis, but with the tarsi and toes disproportionately shorter, and the tibice 

 completely feathered. Adult $ : Pileum uniform lilack, witli a faint gi-eeuish gloss ; remainder of the 

 head ochraceous, growing gradually more rufous on the superciliary region ; nape briglit rufous, becoming 

 nearly chestnut on the lower portion ; sides of the neck like the cheeks. Chin and throat immaculate 

 pure white, the lower part of the latter with a very faint wash of pale buff medially ; foreneck creamy 

 white, with a narrow mesial stripe of grayish brown. Sides of tlie breast brownish black, the 

 feathers tippt-d with light fulvous ; remaining lower parts white, tinged with light creamy buff, most 

 distinct laterally ; tibi;e deep fulvous ; lining of the wings grayish white, purer white anteriorly, where 

 is a spot of mixed ochraceous and dusky on tlie carpal joint ; axillars ash-gray ; under-surface of the 

 remiges similar, but deeper. Back and scapulars glossy black, with a faint green reflection, the outer 

 row of interscapular feathers edged exteriorly with light buff, forming, when the featlrers are disarranged, 

 a somewhat V-shajied mark, defining the lateral and posterior boundaries of the interscapular region. 



VOL. I. — 10 



