small class of bilaterally symmetrical marine forms comprising the tooth shells. 由两边对称的海洋掘足纲软体动物组成的一个小纲。
Bilaterally symmetrical, the nose is definitely the mole's most striking feature. 鼻子无疑是是这种鼹鼠最引人注目得特点。
Of or relating to diatoms of the class Pennales， distinguished by bilaterally symmetrical form. 硅藻的属于或有关以双侧对称形状著名的硅藻的
stout orchid of central California to northern Washington having racemes of white fragrant bilaterally symmetrical flowers. 壮的兰花, 有总状花序, 白色, 芳香的小花对称开放。