An order of irregular sea urchins, usually having a more or less heart-shaped shell with four or five petal-like ambulacra above.
Any structure having a flowerlike form; especially, the group of five broadambulacra on the upper side of the spatangoid and clypeastroid sea urchins.
One of the expanded ambulacra which form a rosette on the black of certain Echini.
Defn: An order of irregular sea urchins, usually having a more or less heart-shaped shell with four or five petal-like ambulacra above.
Defn: One of the expanded ambulacrawhich form a rosette on the black of certain Echini.
D); the ambulacrathus formed are continuous from the peristome to the apical system of plates; the hydropore is connected with a definite plate of that system, and thus marks a secondary bilateral symmetry.
Spencer to have had in its ambulacraan inner as well as an outer series of plates.
The stereom of the radials and deltoids on each side of the ambulacra is thrown into folds, running across the radio-deltoid suture, and hanging down into the thecal cavity as respiratory organs (hydrospires).
A portion of these ambulacra are made fast by suction while the rest of the body is drawn forward; then the first are relaxed and the process repeated, thus they travel in the deep waters.
In the same way the animal creeps up perpendicular rocks, which is accomplished by means of these ambulacra and suckers.
These ambulacra are very numerous, disposed in rows along the under surface of the rays; thus in A.
The ambulacra run down the sides of the cone in straight lines, and around the base is a depressed area which emphasizes a thick border which extends around the scalloped margin.
By the alternating movements of the ambulacra the animal is dragged slowly along and moves with a gliding motion.
The ambulacra are small spines without suckers, which emanate from the sides or margins of the arms and do not serve for walking.
In the four ambulacra on the ground floor, were shops, taverns, stables, and rooms for refreshments, and places where perfumes were burned.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "ambulacra" in a variety of sentences. We hope that you will now be able to make sentences using this word.
