Note:  Do not rely on this information. It is very old.


Holectypus, a sea urchin common in the oolitic limestones and clays of England. It has a low rounded or conical form, a large moutii with the anus on the lower side or just on the lower angle of the margin. The interesting point about the genus is the possession of jaws, which in the allied Galerites, etc., are absent.