释义 |
psi·lop·si·da \sīˈläpsədə\ noun plural Usage: capitalized Etymology: New Latin, from psil- + -opsida (as in lycopsida) : a subdivision of Tracheophyta comprising vascular plants with no roots, leaves only partially differentiated or lacking, no leaf traces, a usually protostelic vascular cylinder, and the sporangia merely terminal enlargements of the stem — compare lycopsida, pteropsida, sphenopsida |