Gemma

I know of no other genera with such intramarginal formation of true gemmae.

Gemmae are frequently longer than wide or of irregular shape. According to Degenkolbe, gemmae-bearing leaves are always different in form from normal leaves.

In Marchantia polymorpha, high temperature promotes germination of gemmae (Dacknowski, 1907), and heat absorbed by the gemmae accelerates their germination (Fitting, 1942).

Gemma. A curious name. He didn't think he had ever come across it before. She would have an outlandish name, either because her equally eccentric parents had labelled her with it or—more likely—she had adopted it herself on the grounds of originality.

Gemma gave him another gushing smile. She wanted to make amends for almost fouling up Blake's deal. "Gemma. What a beautiful name. You are indeed a jewel."