A demand has sprung up, principally in Japan (for the manufacture of buttons) for the trochus shell (a univalve
spiral shell), which is to be found in considerable quantities on the reefs that spread everywhere in these waters.
In 2010 Pierburg purchased the rights to the 'UniValve
' variable valve system from enTec Consulting GmbH, presently readying it for series production on behalf of a number of customers.
Another development they're pursuing, which was originally conceived by enTec Consulting GmbH (entecconsuhing-de), is a variable valve control system called "UniValve
." This is an electromedical system that provides continuous variation of valve opening with simultaneous adjustment of the valve lift.
Take the "left-handed whelk shell", more correctly termed the reverse univalve
shell, for example.
Supplement to number one of "A monograph of the limniades, or freshwater univalve
shells of North America", containing descriptions of apparently new animals in different classes, and the names and characters of the subgenera in Paludina and Anculosa.
speculum is far superior to all others for