ClipArt ETC
"Cross section through the thallus of Marchantia. j, stoma leading into a relatively large air-chamber in which arise numerous cells with chloroplasts, k; l, l, cells forming partitions between the air-chambers; m, cells destitute of chloroplasts and with numerous oblong pits; h, upper, and i, lower epidermis." -Stevens, 1916

Marchantia Thallus

"Cross section through the thallus of Marchantia. j, stoma leading into a relatively large air-chamber…