A PTERION, APTERIUM

(Lat.), n. n. ’ri?-o7n, -uSm(u‘m). -Ger., Federrain. A naked space on the skin of a bird. (i. e., one having no contour-feathers). [Nitzsch (A, 322).]—A. alæ inferius. Ger., unterer Flügelrain. An a. extending over the lower part of the upper arm, the great wing-membrane, the axillary wing-membrane, and sometimes the forearm of birds. [L, 194.] = alæ super i us. An a. extending over a portion of the upper arm and the great wing-membrane of birds which separates the axillary tract from the other feathered parts. [L, 194.]—A. coll i laterale. Ger., Hal eitenrain. Ana. upon the side of the neck of birds; it varies greatly in extent according to the genus. [L, 194.]—A. crurale. Ger., Unterschenkelrain. An a. at the upper end of the tibial region of birds. [L, 194.) —A. mesogastræi. An a. in the middle line of the ventral surface of birds. [L, 194.J—A. nuchale. An a. at the nape of the neck of some birds. [L, 194.] —A. spinale. Ger., Riicl tsrain. An a. sometimes occurring upon the backs of birds. [L, 194.]—A. temporale. An a. sometimes occurring upon the heads of birds. [L, 194.)—A. trunei laterale. Ger., Rumpfseitenrain. An a. on the side of the trunk of birds. [L, 194,]