74 
ORNITHOLOGISTS' COMPENDIUM. 
Decomposed, a. Said of a feather when the barbs are separated, not 
forming a continuous or compact web. 
Decum'bent (L. decum'bens), a. Hanging downward; drooping. 
Decus'sate (L. decussa'las) , a. Crossed ; intersected. (Plate XV. fig. 16.) 
Deep Chrome Yellow, n. A very deep but not brilliant yellow color. 
(Winsor & Newton's "deep chrome," or Schoenfeld's "goldgelb" or 
" mittel chromgelb.") (Plate VI. fig. 9.) 
Del'toid (L. deltoid'eus), a. Triangular, or shaped like the Greek character 
" Delta," A. (Plate XIV. fig. 14.) 
Dentate (L. denta'tus), a. Toothed. (Plate XV. fig. 20.) 
Dentictilate (L. denticula'tus), a. With small teeth. 
Dentig'erous (L. dentiger'), a. Bearing teeth. 
Dentirostres (L.), n. An artificial or arbitrary group in classifications, 
the members of which have the maxilla more or less notched near the 
tip. 
Dentirostral (L. dentiros'tris) , a. Tooth-billed; pertaining to the Denti- 
rostres. 
Denudation, a. Nakedness. 
Deplum'ate (L. depluma'tus), a. Bare of feathers. 
Depress'ed (L. depres'sus), a. Flattened vertically; broader than high. 
(Opposite of compressed.) 
Der'mal (L. derma' lis), a. Pertaining to the skin. 
Desquamation, n. Peeling or scaling off. 
Di- (in composition). Twice; double (as dichromatic = two colored). 
Diagnosis, n. A condensed statement of the characters which are ex- 
clusively applicable to a species, genus, or higher group ; a description 
which omits all non-essential characters. 
Diagnostic, a. Pertaining to diagnoses; exclusively applicable, or 
distinctly characteristic. 
Dichot'omous, a. Paired, or by twos. 
Dichromatic, a. In descriptive Ornithology a species is said to be di- 
chromatic when it exists in two distinct plumages which are entirely 
independent of sex, age, or season. These distinct plumages were 
formerly, in the case of most dichromatic birds, supposed to represent 
distinct species, and the nature of their real relationship is a com- 
paratively recent discovery. Familiar examples of dichromatism are 
the rufous and gray forms of the little Screech Owl (Scops asio), and 
the white and bluish or dusky forms of some Herons (as Ardea 
occidentalis and Dichromanassa rufa). 
Dichrom'atism, n. The state of existing in two distinct phases of color- 
ation, which are wholly independent of the usual causes of color 
differences (as sex, age, and season). Dichromatism among birds is 
somewhat analogous to dimorphism in insects. 
Dig'itigrade, a. Walking on the toes. (Applicable to most birds.) 
Didactyle, 
Didac'tylous, 
(L. didac'tylus), a. Two-toed, as the Ostrich. 
