Turriculated. Having the form of a tower. 



Turreted. Having the form of a tower. 



Umbilicated. Having an opening in the base of the shell. 



Undulated. Having undulations or waves, as the surface of some Unios. 



Univalve. Having the shell composed of a single piece, as a snail. 



Varicose. Swollen or enlarged. 



Vascular. Containing or made up of blood-vessels. 



Vermiform. Formed like a worm. 



Ventral. The lower border or side. 



Ventricose. Swollen or inflated on the ventral side. 



Vibratile. Moving from side to side. 



Viscous. Sticky. 



Vitreous. Resembling glass, as some snails. 



Viviparous. Bringing forth the young alive as in the genera Vivipara and 



Campeloma. 



3 Male. The astronomical sign for the planet Mars. 

 ? Female. The astronomical sign for the planet Venus. 



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