~L. perlatum~ Persoon is also a common puff-ball; it is pestle-shaped or top-shaped, whitish or tan with minutely roughened, globose spores measuring 4 µm in diameter. The fruit-body is covered in a mixture of large and small, fragile spines which leave a network when rubbed off. It grows in woods and on heaths. ~L. foetidum~ Bonorden is similar to _L. perlatum_, but the spines are umber or vandyke-brown; it also grows both in woods and upland pastures, particularly the latter. _Illustrations_: _L. pyriforme_--Hvass 316; LH 219; NB 155³; WD 109³. _L. perlatum_--Hvass 315; LH 217; NB 155²; WD 110². [Illustration: Plate 62. Puff-balls] ~Langermannia gigantea~ (Persoon) Rostkovius Giant puff-ball _Fruit-body_: diameter 300-450 mm (-1,050 mm). _Description_: Fruit-body: round or slightly flattened on the top, smooth or cracked into small scales, white but becoming flushed yellowish with age and finally olive-brown when old, frequently the outer layer dries and breaks away to expose the powdery spore-mass within. Stem: absent or only present as a small cone of tissue. Spore-mass: whitish, cream-coloured and finally olive-brown. Spores: small, brownish, minutely warted and spherical, 4-5 µm in diameter and intermixed with thick-walled, branched, brown hyphae, 3-5 µm broad. _Habitat_ & _Distribution_: On the ground in copses, at the edges of woods, under hedges or on refuse tips, and sometimes in gardens. It may appear in the same place year after year, and has been recorded growing beneath the rafters in houses. _General Information_: When young it is white inside or cream-coloured before the spores have developed and can then be cut into slices and cooked. I have seen it on sale in markets in N. America and it is collected for food by many in Europe. Its pumpkin-shape with a circumference of anything up to 1,050 mm makes this fungus easily recognisable. The number of spores produced by a fruit-body measuring 400 × 280 mm has been calculated by A. H. R. Buller as 7,000,000,000,000 spores! ~Calvatia utriformis~ (Fries) Jaap (= _C. caelata_ (Persoon) Morgan) has a goblet-like shape and a distinct, sterile base composed of large cells with a prominent membrane separating them from the spore-mass; the spores are 4-5 µm diameter, smooth and spherical. ~C. excipuliformis~ (Fries) Perdeck (= _C. saccata_ (Vahl.) Morgan) is pestle-shaped with a well developed stem. The spore-mass is composed of warted, globose spores, 4-5 µm in diameter. ~Bovista nigrescens~ Persoon is very similar in shape to the Giant puff-ball, but is very much smaller; it lacks a stalk, being attached to the substrate only by mycelial cords. It commences white, but then darkens to become purplish brown at maturity when it also breaks from its moorings and rolls about in the wind. The last three species are found on heaths, in pastures or on the ground in woods.