The univalves which possess a siphon are, for the most part, carnivorous, and are often most voracious creatures. |
The whorls of spiral univalves generally take an oblique direction in reference to the imaginary axis of the shell. |
Thus, all rostroconches and some helcionellacean univalves technically become stem group bivalves. |
Yet, since each of these three univalves has been this day created, these inferences are deceptive. |
Some mollusks have only one shell and they are called univalves or gastropods. |
Beads made from the columell of univalves have generally a number of distinguishing characteristics. |