Temnopleuridae

Temnopleuridae, a family of Sea-urchins belonging to the order Diadematoida, and including those forms which have the month situated on the centre of the lower surface, and the anus opposite it; the mouth is armed with jaws, and along the sutures between the plates of the test are numerous pits or grooves. The former occur in the sub-family Temnopleurinae, and the latter in the Glyphocypninae. The family is now widely distributed, inclndes twenty-two genera, and ranges from the Cretaceous period onward.