'The title club-moss' is the common name for

Explanation:

Lycopodium:

• Belongs to the class Lycopsida of group Pteridophyta.
• Commonly called ''club moss''.
• The plant body is differentiated into roots, stems, and leaves but the stem is not divided into nodes and internodes.
• It is used for making homeopathic medicine.
• The spores of lycopodium are used for cleaning the lens of a microscope.

Mistake Points

• Little club moss - Selaginella
• Club Moss - Lycopodium

Additional Information

• Equisetum (Pipe) also called ''horse tail'' is included in the class sphenopsida.
• The plant body is differentiated into roots, stems, and leaves. Roots are adventitious.
• Their stem is jointed i.e. their stem is divided into nodes and internodes.
• Selaginella or spike moss are called resurrection plants because most of the species of selaginella are drought escapers i.e. do not face drought conditions, complete their life cycle in the short wet season 
• Marsilea is a heterosporous pteridophyte. The formation of spores takes place in sporangia. Sporangia are formed at the abaxial surface of leaves.
• The leaves on which sporangia are formed are called sporophylls.