Search the Dictionary

The first or anterior segment of the thorax in insects. See Illusts. of Butterfly and Coleoptera.

gments, into which the mesoblast of the vertebrate embryo breaks up on either side of the anterior part of the notochord; a mesoblastic, or protovertebral, somite. See Illust. of Ectoderm.

A class of Mollusca in which the anterior lobes of the foot are developed in the form of broad, thin, winglike organs, with which they swim at near the surface of the sea.

The ventral and anterior of the three principal bones composing either half of the pelvis; sharebone; pubic bone.

, or elevations, on the dorsal side of the midbrain of most mammals; the optic lobes. The anterior pair are called the nates, and the posterior the testes.

The act or process of removing a cataract, by applying the needle to its anterior surface, and depressing it into the vitreous humor in such a way that front surface of the cataract becomes the upper one and its back surface the lower one. Dunglison.

palm of the hand. -- Recurrent sensibility (Physiol.), the sensibility manifested by the anterior, or motor, roots of the spinal cord (their stimulation causing pain) owing to the presence of sensory fibers from the corresponding sensory or posterior roots.

The anterior, often spinelike, prolongation of the carapace of a crustacean, as in the lobster and the prawn.

Of or pertaining to the sacrum and that part of the vertebral column immediately anterior to it; as, the sacrovertebral angle.

Having the anterior nostrils prolonged backward in the form of a slit.

Having the anterior surface of the tarsus covered with scutella, or transverse scales, in the form of incomplete bands terminating at a groove on each side; -- said of certain birds.

Having the anterior toes joined only part way down with a web; half-webbed; as, a semipalmate bird or foot. See Illust. k under Aves.

One older in office, or whose entrance upon office was anterior to that of another; one prior in grade.

e, distinguished by the posterior extremities moving in the order of a fast walk, and the anterior extremities in that of a slow trot. Stillman (The Horse in Motion.)

The anterior prolongation of the margin of any gastropod shell for the protection of the soft siphon.

border of Gephyrea, including those which have the body unarmed and the intestine opening anteriorly.

The anterior prolongation of the head of a gastropod; -- called also rostrum.

ther intense light. -- Solar plexus (Anat.), a nervous plexus situated in the dorsal and anterior part of the abdomen, consisting of several sympathetic ganglia with connecting and radiating nerve fibers; -- so called in allusion to the radiating nerve fibers. -- Solar spots. See Sun spots, under Sun. -- Solar syste…

shell with four or five petal-like ambulacra above. The mouth is edentulous and situated anteriorly, on the under side.

bone; sphenethmoidal. Sphenethmoid bone (Anat.), a bone of the skull which surrounds the anterior end of the brain in many amphibia; the girdle bone.