Interambulacral

In these, as in the Crinoids, the interambulacral plates are absent, and the interambulacral spaces are filled by an encroachment of the ab-oral region upon them. ❋ Various (N/A)

Echinoderms the interambulacral plates are absent; there are no rows of plates of a different kind alternating with the ambulacral ones, as in the Sea-Urchins and the Star-Fishes, but the ab-oral region closes immediately upon the ambulacra. ❋ Various (N/A)

In technical language, the surface from which these fleshy threads protrude, are called ambulacral areas, and the spaces between, interambulacral areas. ❋ Unknown (1858)

[CIDARIS CAROLINENSIS] small tubercles with two in a row, and interspersed with minute ones, which appear in some places to be arrayed in subordinate rows; interambulacral areas wide, covered with small subequal and rather prominent tubercles, among which minute granules are scattered; area about four times as wide as the former; plates pentagonal, supporting two rows of large perforated primary tubercles, surrounded by plain circular zones; miliary zone concave or depressed. ❋ Unknown (1858)

-- The ambulacral areas are narrow, but the poriferous zones are rather wide; and the interambulacral areas are about four times as wide as the ambulacral. ❋ Unknown (1858)

[GONIOCLYPEUS SUBANGULATUS] somewhat pentangular; posterior or anal orifice lateral, or upon the superior face; interambulacral area grooved, with the continued area beneath projecting; interambulacral areas sub-angulated; mouth rather narrow or small, central; peristome angular, and surrounded by five angular prominences, which terminate in the interambulacral areas, between which is a rosette, perforated by seven pairs of pores, with three odd ones at the end of each petal; ambulacra petaloid and closed; the prolonged zone provided with alternating pores as far as the base; pores connected by oblique grooves; interambulacral wide; plates large, and nine or ten in a column. ❋ Unknown (1858)

"Body broadly ovate, elevated and truncate posteriorly; back oblique; dorsal impression lanceolate; scutab area very slightly excavated; ambulacral spaces broad, triangular, depressed; interambulacral spaces slightly convex; anteal furrow broad and shallow, sides slightly gibbous; sub-anal impressions broadly ob-cordate; post-oral spinous space broadly lanceolate. ❋ Unknown (1858)