Dactylochirotida
Dactylochirotida is an order of primitive sea cucumbers. Unlike other sea cucumbers, their tentacles are not divided into multiple branches, and the body is enclosed within a flexible shell-like structure called a test.
英汉双解词典包含3607232条英汉词条，基本涵盖了全部常用单词的翻译及用法，是英语学习的有利工具。