_General Information_: _Cyathus_ differs from _Crucibulum_ in the more complex fruit-body which consists of three layers, and the peridioles forming on distinct stalks. Two species are frequently seen: _Cyathus striatus_ Persoon has a grey, fluted inner surface to the cup and strongly hairy red-brown outer surface; the spores measure 16-22 × 9-10 µm. _Cyathus olla_ Persoon has a smooth, shiny, grey surface and minutely silky, yellowish grey outer surface. _C. striatus_ is found on twigs, and about dead stumps; _C. olla_ is more frequent in gardens on herbaceous debris and dead pieces of perennial flowers--or even in plant pots. ~Sphaerobolus stellatus~ Persoon is more distantly related and grows on decaying leaves, bracken fronds, partially buried twigs and dung. It is an intriguing fungus because it possesses a remarkable spore-dispersal mechanism. The inner layer of the fruit-body when ripe suddenly turns inside out catapulting the inner spore-mass to distances of anything up to 4,200 mm, that is a distance of 1,000 times the size of the fruit-body. The fruit-body is externally whitish or pale yellow, but this layer splits into lobes like a star exposing the bright orange inner surface and pale spore-mass. _Illustrations_: _Crucibulum laeve_--LH 223; WD 111⁷. _Cyathus striatus_--LH 223; WD 111⁹. _Sphaerobolus stellatus_--LH 223; WD 111⁵. [Illustration: Plate 66. Bird’s nest fungi] E. CUP FUNGI AND ALLIES _General Notes._ The Ascomycetes differ from all the other fungi so far dealt with in that the spores develop enclosed in a microscopic envelope or sac--called the ascus. Usually eight spores are produced in each ascus and they are often dispersed violently into the air. Elf-cups and morels are typical Ascomycetes, but the group also includes innumerable minute forms of the microscopic fungi, small discs, minute flask-like structures, some of which are parasitic on leaves and stems of higher plants. In number the large species of Ascomycetes are few when compared with the others and therefore can only be given but a mention in the present account. When collected the Ascomycetes can be distinguished from the Basidiomycetes by simply examining a slice of the spore-producing tissue where the tell-tale asci will be seen (see p. 21). If the fruit-body is placed in a tin when collected and opened in a warm room all the mature asci explode at once producing a cloud of spores visible in the air immediately over the fruit-body. ~Aleuria aurantia~ (Fries) Fuckel Orange-peel fungus or Scarlet elf-cup _Fruit-body_: diameter 25-50 mm. _Description_: Fruit-body: cup-shaped then undulating and becoming flattened, irregular, sometimes split and lacking a stem. Inner surface: bright orange. Outer surface: whitish and minutely downy. Flesh: thin and white.