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Pertaining to acnodes.

to ambulacra; avenuelike; as, the ambulacral ossicles, plates, spines, and suckers of echinoderms.

One of the radical zones of echinoderms, along which run the principal nerves, blood vessels, and water tubes. These zones usually bear rows of locomotive suckers or tentacles, which protrude from regular pores. In star fishes they occupy the grooves along the under side of the rays.

ondition of decreased irritability of a nerve in the region of the positive electrode or anode on the passage of a current of electricity through it. Foster.

ve element, or the element which, in electro- chemical decompositions, is evolved at the anode; -- opposed to cation. Faraday.

ding the annelids and allied groups; sometimes made to include also the helminths and echinoderms. [Written also Annuloidea.]

The stipe when developed into an internode between calyx and corolla, as in the Pink family. Gray.

One of the nodes or joints, as in cane and maize.

other, grandfather and grandmother, etc., are in the line direct ascending. -- Ascending node having, that node of the moon or a planet wherein it passes the ecliptic to proceed northward. It is also called the northern node. Herschel. -- Ascending series. (Math.) (a) A series arranged according to the ascending powe…

A genus of echinoderms.

A class of Echinodermata including the true starfishes. The rays vary in number and always have ambulacral grooves below. The body is starshaped or pentagonal.

One side of an echinoderm, including a pair of ambulacra, in distinction from the opposite side (trivium), which includes three ambulacra.

ich the electric current passes out of the electrolyte; the negative pole; -- opposed to anode. Faraday. Cathode ray (Phys.), a kind of ray generated at the cathode in a vacuum tube, by the electrical discharge.

ived upon the other and brought to the principal focus. -- Conjugate point (Geom.), an acnode. See Acnode, and Double point. -- Self-conjugate triangle (Conic Sections), a triangle each of whose vertices is the pole of the opposite side with reference to a conic.

A large class of Echinodermata, including numerous extinct families and genera, but comparatively few living ones. Most of the fossil species, like some that are recent, were attached by a jointed stem. See Blastoidea, Cystoidea, Comatula.

Possessing, or characterized by, a crunode; -- used of curves.

-- Cycle of eclipses, a priod of about 6,586 days, the time of revolution of the moon's node; -- called Saros by the Chaldeans. -- Cycle of indiction, a period of 15 years, employed in Roman and ecclesiastical chronology, not founded on any astronomical period, but having reference to certain judicial acts which too…

signs (Astron.), those through which the planets descent toward the south. -- Descending node (Astron.), that point in a planet's orbit where it intersects the ecliptic in passing southward. -- Descending series (Math.), a series in which each term is numerically smaller than the preceding one; also, a series arrange…

y possess most of the properties of double points (see Conjugate). They are also called acnodes, and those points where the branches of the curve really cross are called crunodes. The extremity of a cusp is also a double point. -- Double quarrel. (Eccl. Law) See Duplex querela, under Duplex. -- Double refraction. (Op…

Belonging to that space of time in which the moon performs one revolution, from ascending node to ascending node. See Dragon's head, under Dragon. [Obs.] "Dracontic month." Crabb.