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eral setæ, or spines, on most or all of the segments. They are divided into two principal groups: Oligochæta, including the earthworms and allied forms, and Polychæta, including most of the marine species.

in the middle and upper Silurian rocks. The tubular corallites are united side by side in groups, looking in an end view like links of a chain. When perfect, the calicles show twelve septa. -- Chain coupling. (a) A shackle for uniting lengths of chain, or connecting a chain with an object. (b) (Railroad) Supplementary…

The group of seven stars, commonly called the Dipper, in the constellation Ursa Major, or Great Bear. See Ursa major, under Ursa.

mung River, along which the rocks are well developed. It includes the Portage and Chemung groups or epochs. See the Diagram under Geology.

A zigzag molding, or group of moldings, common in Norman architecture. Chevron bones (Anat.), The V-shaped subvertebral arches which inclose the caudal blood vessels in some animals.

One of a group of gastropod mollusks, with a shell composed of eight movable dorsal plates. See Polyplacophora.

cohols (and especially glycerin) by the substitution of chlorine for one or more hydroxyl groups.

The name of a group of minerals, usually of a green color and micaceous to granular in structure. They are hydrous silicates of alumina, iron, and magnesia. Chlorite slate, a schistose or slaty rock consisting of alumina, iron, and magnesia.

A group of fishes, characterized by cartilaginous fins and skeleton. It includes both ganoids (sturgeons, etc.) and selachians (sharks), but is now often restricted to the latter. [Written also Chondropterygia.]

Making Christ the center, about whom all things are grouped, as in religion or history; tending toward Christ, as the central object of thought or emotion. J. W. Chadwick.

Any chemical group or residue (as NO

An artificial, yellow, crystalline dye, C6H5N2.C6H3(NH2)2. Also, one of a group of dyestuffs resembling chrysoïdine proper.

One of the quinine group of alkaloids, found especially in red cinchona bark. It is a white crystalline substance, C19H22N2O, with a bitter taste and qualities similar to, but weaker than, quinine; -- sometimes called also cinchonidia.

One of the quinine group of alkaloids isomeric with and resembling cinchonidine; -- called also cinchonia.

e American lower Silurian system. The rocks are well developed near Cincinnati, Ohio. The group includes the Hudson River and Lorraine shales of New york.

The group of Thysanura which includes Lepisma and allied forms; the bristletails. See Bristletail, and Lepisma.

A circular group of persons; a ring.

s shell composed of several pieces. From the opening of the shell the animal throws out a group of curved legs, looking like a delicate curl, whence the name of the group. See Anatifa.

The lowest group of vertebrates; -- so called from the cirri around the mouth; the Leptocardia. See Amphioxus.

A group of individuals ranked together as possessing common characteristics; as, the different classes of society; the educated class; the lower classes.