Part 153

HY´BRIDIZE. To cross and bear mongrel offspring.

HY´OID, HYOID´EAN, a. Pertaining to the os hyoides or tongue-bone, or, more generally, to the tongue itself.

HYPAPOPH´YSIS, n. Bony process from the under side of a vertebra, sometimes very large, as in the loon.

HYPER- (in composition). Same as super- (which see).

HYPERBO´REAN, a. Northern; boreal.

HYPERCHROM´ATISM, n. State of unusually increased or intensified coloration.

HYPER´TROPHY, n. Inordinate enlargement of a part or organ, due to excessive nutrition. The opposite of atrophy, or the wasting away of an organ through deficient nutrition.

HYPO- (in composition). Same as sub- (which see).

HYPOCHON´DRIUM, n. The flank. (Oftener used in the plural, hypochondria, flanks.) (67.)

HYPODAC´TYLUM, n. Soles of the toes. (118.)

HYPOGAS´TRIC, a. Under or behind the belly. (Little used).

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.

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.

IL´EUM, n. Lower portion of small intestine.

IL´IAC, a. Relating to the ilium, or haunch-bone; also, to the ileum.

IL´IUM, n. Haunch-bone; principal bone of the pelvis, forming with the ischium and pubis the os innominatum.

IM´BRICATED, a. Fixed shingle-wise with overlapping edge or end.

IMMAC´ULATE, a. Unspotted; not marked with different colors.

IMMATURE´, a. Not having yet assumed final size, shape, color, or other conditions of the adult.

IMPER´FORATE, a. Not pierced through; also, closed up (said chiefly of the nostrils).

IMPLACEN´TAL, a. Having no placenta. Birds are implacental.