3. Coccobotrys Chod. The cells of this new algal genus are smaller than those of Cystococcus or Protococcus and have no pyrenoid. They were isolated by Chodat from the thallus of Verrucaria nigrescens ([Fig. 24]), and, as they have thick membranes, they adhere in a continuous layer or thallus. Chodat also claims to have isolated a species of Coccobotrys from Dermatocarpon miniatum, a foliose Pyrenolichen.
4. Coccomyxa Schmidle. Cells ellipsoid, also without a pyrenoid. Two species were obtained by Chodat from the thallus of Solorinae and are recorded as Coccomyxa Solorinae croceae and C. Solorinae saccatae.
Coccomyxa subellipsoidea is given[284] as the gonidium of the primitive lichen Botrydina vulgaris ([Fig. 25]). The cells are surrounded by a common gelatinous sheath.
Fig. 24. Coccobotrys Verrucariae Chod. from culture × 800 (after Chodat).
Fig. 25. Coccomyxa subellipsoidea Acton. Actively dividing cells, the dark portions indicating the chloroplasts × 1000 (after Acton).
5. Diplosphaera Bial.[285] D. Chodati was taken from the thallus of Lecanora tartarea and successfully cultivated. It resembles Protococcus, but has smaller cells and grows more rapidly; it is evidently closely allied to that genus, if not merely a form of it.
6. Urococcus Kütz. Cells more or less globose, rather large, and coloured with a red-brown pigment, with the cell-wall thick and lamellate, forming elongate strands of cells ([Fig. 26]). Recorded by Hue[286] in the cephalodium of Lepolichen coccophorus, a Chilian lichen.