Order 8. Cucurbitariaceæ. Perithecia tufted, at first embedded, then breaking through, often situated upon an indistinct stroma.
Orders 9–13. The perithecia remain embedded, and are only liberated by the casting off of the covering layers of the substratum. Stroma wanting.
Order 9. Sphærellaceæ. The species of Sphærella have colourless, bicellular spores. They live upon the leaves of many plants, and develope spherical perithecia upon the fallen leaves.
Order 10. Pleosporaceæ. The conidial-forms of Pleospora herbarum and P. vulgaris form a black covering on various plants, known as “smuts.”—Venturia ditricha occurs on the underside of dry Birch leaves, and perhaps to this belongs the conidial-form, Fusicladium pirinum, which causes the “Rust spots” on Apples and Pears.
Order 11. Massariaceæ.
Order 12. Clypeosphæriaceæ.
Order 13. Gnomoniaceæ. Perithecia, with peak-like aperture. Gnomonia erythrostoma in the leaves of Prunus avium, which turn brown and do not fall in autumn.
Orders 14–18. Stroma generally well developed. The perithecia are embedded in the stroma, but when this is rudimentary, in the substratum.
Order 14. Valsaceæ. Valsa.
Order 15. Diatrypaceæ. Diatrype.