The Collaborative International Dictionary of English v.0.48:

Ventriculite \Ven*tric"u*lite\, n. [See Ventriculus.]
   (Paleon.)
   Any one of numerous species of siliceous fossil sponges
   belonging to Ventriculites and allied genera,
   characteristic of the Cretaceous period.
   [1913 Webster]

   Note: Many of them were shaped like vases, others like
         mushrooms. They belong to the hexactinellids, and are
         allied to the Venus's basket of modern seas.
         [1913 Webster]