Search the Dictionary

mmonly developed, and the cells around it are at first arranged in two layers, -- the ectoderm and endoderm. The group comprises nearly all animals except the Protozoa.

, or otherwise remove, the substratum or foundation of; to lay a mine under; to sap; to undermine; hence, to ruin or destroy by slow degrees or secret means. They mined the walls. Hayward. Too lazy to cut down these immense trees, the spoilers... had mined them, and placed a quantity of gunpowder in the cavity. Sir W.…

oy woolen and fur goods, etc., esp. the larvæ of several species of beetles of the genera Dermestes and Anthrenus. Carpet moths are often the larvæ of Anthrenus. See Carpet beetle, under Carpet, Dermestes, Anthrenus.

the horny scale of plate of epidermis at the end of the fingers and toes of man and many apes. His nayles like a briddes claws were. Chaucer.

vertebrates, connects the medullary tube and the primitive intestine. See Illust. of Ectoderm.

ut eighty feet of shale supporting a greater thickness of limestone, which is gradually undermined by the removal of the shale. See Chart of Geology.

rior part of the base of the skull are developed; the chorda dorsalis. See Illust. of Ectoderm.

A class of star-shaped echinoderms having a disklike body, with slender, articulated arms, which are not grooved beneath and are often very fragile; -- called also Ophiuroida and Ophiuridea. See Illust. under Brittle star.

One of numerous small calcareous structures forming the skeleton of certain echinoderms, as the starfishes.

A combining form meaning thick; as, pachyderm, pachydactyl.

sade cells (Bot.), vertically elongated parenchyma cells, such as are seen beneath the epidermis of the upper surface of many leaves. -- Palisade worm (Zoöl.), a nematoid worm (Strongylus armatus), parasitic in the blood vessels of the horse, in which it produces aneurisms, often fatal.

A pachyderm of the genus Dicotyles.

A chitinous membrane covering the exterior of many shells; -- called also epidermis.

The region surrounding the anus, particularly of echinoderms.

The entire covering of an invertebrate animal, as echinoderm or coelenterate; the integument.

icacy; entanglement; distraction of mind through doubt or difficulty; embarrassment; bewilderment; doubt. By their own perplexities involved, They ravel more. Milton.

, a form of cellular tissue in which the cells are broad and flat, as in some kinds of epidermis.

A mayor, alderman, or other magistrate, in some towns of Italy.

The hindermost dorsal piece of a thoracic somite of an insect; the plate behind the scutellum.

), an opaque and thickened band where the mesoblast first appears in the vertebrate blastoderm.