Illaenus sentence example

illaenus
  • One of the Asaphidae allied to Illaenus, from the Ordovician of East Gothland, Sweden.
    0
    0
  • In this genus the number of segments composing the pygidium is obscured, as also it is in the genus Illaenus, which has as many as ten movable segments preceding the large semi-circular pygidium; but in such forms as Ogygia and Asaphus, which have about eight free segments, the sutural lines on the pygidium indicate that it is composed of about a dozen or more segments.
    0
    0