Thallus foliose with both surfaces corticate and attached by rhizinae. Algal cells _Trentepohlia_. There is but one genus, _Lepolichen_, which has a laciniate somewhat upward growing thallus. Two species, both from South America, have been described, _L. granulatus_ Müll.-Arg. and _L. coccophora_ Hue. The latter has been recently examined by Hue[1041] who finds, on the thalli, cephalodia which are peculiar in containing bright-green gelatinous algae either _Urococcus_ or _Gloeocystis_, one of the few instances known of chlorophyllaceous algae forming part of a cephalodium. _Gloeocystis_ may be the only alga present in the cephalodium; _Urococcus_ is always accompanied by _Scytonema_. The perithecia are immersed in thalline tubercles: Spores colourless, simple, ovoid or ovoid-elongate 1. *Lepolichen Trevis. XIII. _STRIGULACEAE_ A family of epiphyllous lichens inhabiting and disfiguring coriaceous evergreen leaves, or occasionally fern leaves in tropical or subtropical regions. The algae associated are _Mycoidea_ and _Phycopeltis_ (_Phyllactidium_). The only truly parasitic lichen, _Strigula_, belongs to this family: the alga precedes the lichen on the leaves and is gradually invaded by the hyphae of the lichen and altered in character. The small black perithecia are scattered over the surface. In _Strigula_ the lichen retains the spreading rounded form of the alga. The other genera are more irregular. Thallus orbicular in outline 1. *Strigula Fries. Thallus irregular. Perithecia without hairs. Spores colourless. Spores elongate, multi-septate 2. *Phylloporina Müll.-Arg. Spores muriform 3. *Phyllobathelium Müll.-Arg. Spores brown. Spores simple 4. *Haplopyrenula Müll.-Arg. Spores elongate, 1-3-septate 5. *Microtheliopsis Müll.-Arg. Perithecia beset with stiff hairs 6. *Trichothelium Müll.-Arg. XIV. _PYRENIDIACEAE_ The only family of Pyrenocarpineae associated with blue-green algae. The genera of Pyrenidiaceae are all monotypic, only one is common and of wide distribution, _Coriscium_ (_Normandina_ Nyl.). _Pyrenidium_ is the only member that has a fruticose thallus, and that is of minute dimensions. _Eolichen Heppii_, found and described by Zukal, is a doubtful lichen. “_Lophothelium_” Stirton is a case of parasitism of a fungus, _Ticothecium_, on the squamules of _Stereocaulon condensatum_. Algal cells _Scytonema_ or _Stigonema_.