As´ter [Gr. aster, star.]
As-ter-oi´de-a [Gr. aster, star; eidos, form.] Echinoderms having radiating arms with ambulacral grooves below, embracing the true star-fishes.
At´a-vism [Lat. atavus, grandfather.] Reversion; recurrence to an ancestral type.
At´e-les [Gr. ateles, imperfect.]
Au´ri-cles [Lat. auricula, little ear.] A chamber of the heart which receives blood from the veins and transmits it to the ventricle.
A´ves [Lat. pl. of avis, bird.] Birds, a class of vertebrata.
Ba-cil´lus [Lat. bacillum, a little stick.] A genus of bacteria consisting of rod-like cells. They multiply by transverse division and by the formation of endogenous spores. Unicellular plants.
Bac-te´ri-a [Gr. bakterion, stick.] Microscopic unicellular plants. A genus of Schizomycetes (fission-fungi).
Bal-a-no-glos´sus [Gr. balanos, acorn; glossa, tongue.] Supposed by some biologists to belong to the Chordata.
Beams [AS. beam, tree.] The main stem of a deer’s antler.