GLOSSARY OF TECHNICAL TERMS. 103 
Prus'sian Blue, n. A very intense and rich blue color, darker and more 
greenish than ultramarine and cobalt. Similar to, but less pure than, 
Antwerp blue, and not a reliable color. 
Psilopae'des (L.), n. A more or less artificial group of birds born weak 
and helpless, and further distinguished by a scant growth of down 
affixed to the undeveloped pterylaj, or future feathers, to which it is 
temporarily attached. The Passeres and most of the Picarice belong 
to this group. (Synonymous with Gymnopcedes.) 
Psilopse'dic, a. Pertaining to, or having the nature of, the Psilopsedes. 
Psitta'ci (L.), n. A very natural group of birds, comprising the Parrot- 
tribe only. 
Psittacomorph'se (L.), n. The Huxleyan name, meaning " Parrot formed/' 
for the order Psittaci. 
Pterygia (L. ; pi. ptery'laz), n. An area or tract of the skin on which 
feathers grow. A " feather tract." 
Pterylog'raphy, n. A description of the plumage, with reference to the 
distribution of the feather-tracts or pterylae. 
Pterylo'sis (L.), n. The plumage, considered with reference to its 
distribution on the skin. 
Ptilopae'des (L.), n. A more or less artificial group of birds, instituted 
by Professor Sundevall, including those which at birth are covered 
with down. (Synonymous with Dasypcedes.) 
Ptilopae'dic, a. Pertaining to or having the character of Ptilopcedes. 
Clothed at birth with down, like the chick of the domestic fowl, a 
duckling, or a gosling. 
Ptilo'sis (L.), n. Plumage. 
Pul'lus (L.), n. A chick. Applied to the downy young of Ptilopsedic 
or Praacocial birds. 
Punc'tate (L. puncta'tus), a. Dotted. (Plate XV. fig. 12.) 
Pu'pil (L. pupil'la), n. The central black (or dark blue) spot or disk of 
the eye, enclosed within the iris. (Plate XII. fig. 10.) 
Pur'ple (L. purpu'reus), n. A color intermediate between red and blue, 
or produced by the combination of these colors. 
Pygopo'des (L.), n. A group of swimming birds, containing the families 
Podicipididce, Colymbidce, and Alcidce, distinguished by the extreme 
posterior position of the legs. 
Pygop'odous, a. Pertaining to or having the character of the Pygopodes. 
Pyrlform (L. pyrifor'mis), a. Pear-shaped. (Plate XIV. fig. 17 ; plate 
XVI. fig. 7.) 
Q. 
Quadran'gular (L. quadrangula'ris), a. Four-angled, or square. 
Quad'rate (L. quadra'tus), a. Square. (Plate XIV. fig. 2.) 
Quill, n. As generally used, one of the primary remiges ; and perhaps 
best so restricted. 
