Sentence Examples


  • - Ambulacrals simple, each with one or two pores, which sometimes pass between rather than through the plates, in 2 columns; interambulacrals, unior multi-tuberculate, in numerous (say io or more) columns, none passing on to peristome; mouth central with jaws, no external gills or sphaeridia; position of anus doubtful, acyclic, i.e.
  • Always), radiate from a central peristome between five interradial deltoid plates, and are edged by alternating side-plates bearing brachioles, to which side-branches pass from the grooves.
  • Grooves and peristome protected by small plates, which can open over the grooves.
  • - Blastoidea in which the thecal plates have assumed a definite number and position in 3 circlets, as follows: 3 basals, 2 large and I small; 5 radials, often forkshaped, forming a closed circlet; 5 deltoids, interradial in position, supported on the shoulders or processes of the radials, and often surrounding the peristome with their oral ends.
  • 12, D); the ambulacra thus 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.
 

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