Rhizonych´ium, n. Terminal bone of a toe bearing a claw. (122.) (Little used.)
Rhom´boid, a. Lozenge-shaped. Name of a muscle of the shoulder-blade.
Ric´tus, n. Gape of the mouth.
Ridge, n. Culmen (which see). (20.)
Ri´ma, n. Outline of a slit-like opening.
Ri´ma Glot´tidis, n. Opening of the glottis.
Ri´ma Oris, n. Equivalent to Commissure (which see).
Ros´trum, n. Bill; beak; projecting forepart of head of birds; of two jaws, upper and lower, consisting of a frame of certain bones over which is stretched unfeathered skinny or horny membrane, the rhamphotheca. (9.)
Round´ed (tail), a. Having the central feathers longest, the rest successively gradually and slightly shorter. A tail is double-rounded when, with central feathers shorter than the next, the rest are graduated as before.