Spores elongate, septate, cells wider than long. Paraphyses unbranched, filiform. Spores multi-septate, colourless 13. Graphis Adans. Spores multi-septate, brown 14. Phaeographis Müll.-Arg. Spores muriform, colourless 15. Graphina Müll.-Arg. Spores muriform, brown 16. Phaeographina Müll.-Arg. Paraphyses clavate, warted at tips 17. *Acanthothecium Wain. Paraphyses branched, interwoven above 18. *Helminthocarpon Fée. Thallus with _Phycopeltis_ gonidia (epiphyllous). Spores elongate, 3-9-septate, colourless 19. *Opegraphella Müll.-Arg. Spores elongate, 1-septate, brown 20. *Micrographa Müll.-Arg. XX. _CHIODECTONACEAE_ Specially distinguished in this subseries by the grouping of the somewhat rudimentary apothecia in pseudostromata in which they are almost wholly immersed. In form they are roundish or linear; the spores are septate or muriform. The thallus is thinly crustaceous and continuous: in _Glyphis_, _Sarcographa_ and _Sarcographina_ there is an amorphous upper cortex, the other genera are non-corticate. Algal cells are _Trentepohlia_ with the exception of two epiphyllous genera associated with _Phycopeltis_. Genera and species are mostly tropical. _Sclerophyton_ with five species is represented in Europe by a single British specimen, _S. circumscriptum_. The form of the paraphyses is a distinguishing character of the genera. Thallus with _Trentepohlia_ gonidia. Paraphyses free, unbranched. Spore cells short or almost globose. Spores elongate, multi-septate, colourless 1. Glyphis Fée. Spores elongate, multi-septate, brown 2. *Sarcographa Fée. Spores muriform, brown 3. *Sarcographina Müll.-Arg. Spore cells longer and cuboid. Spores muriform, colourless 4. *Enterodictyon Müll.-Arg. Paraphyses branched, interwoven above. Spores elongate, multi-septate, colourless 5. Chiodecton Ach. Spores elongate, multi-septate, brown 6. Sclerophyton Eschw. Spores muriform, colourless 7. *Minksia Müll.-Arg. Spores muriform, brown 8. *Enterostigma Müll.-Arg. Thallus with _Phycopeltis_ gonidia (epiphyllous). Paraphyses free. Spores unequally 2-celled, colourless 9. *Pycnographa Müll.-Arg. Paraphyses branched, interwoven above. Spores elongate, multi-septate, colourless 10. *Mazosia Massal. XXI. _DIRINACEAE_