Hypognath´ous, a. Having the under mandible longer than the upper, as the black skimmer.
Hypopti´lum, n. Supplementary plume, or accessory plume, springing from the same barrel of the main feather. Generally found, but wanting in many families, and always on the quills of the wings and tail. Synonymous with hyporrhachis as generally used.
Hypora´dii, n. pl. Barbs of the hypoptilum.
Hyporrha´chis, n. Aftershaft; stem or scape of the supplementary plume. Generally used for the whole of such accessory feather, but best thus restricted.
Hypoth´esis, n. A reasonable presumption or supposition taken as premise of an argument, or as probably true, to account for what is not understood. As it does not necessarily rest upon fact, it has not the weight or dignity of theory.
Hypothet´ical, a. Reasonably presumptive: logically supposititious; conditional; assumed without proof but with fair probability.
I.
Identifica´tion, n. Act or process of determining to what species a specimen or a name belongs; the determination so made.
Iden´tify. To determine the name of a specimen or of a species; to ascertain the identity of a certain specimen with a name, or name with a certain species.
Igno´ble, a. Said of hawks lacking the special qualities of those used in falconry.