42
THE MYCETOZOA:
spring, and always very attractive from its brilliantly iridescent
sporangia.
L. violaceum (Fries) Rost.—Not common ; on sticks, dead
leaves and mossy stumps, appearing chiefly in autumn and
winter.
L. arcyrionema Rost.—A widely distributed species, but
only once recorded from Essex ; a small growth of the silvery
sporangia was found on a hornbeam stump in Gilbert Slade in
July 1892.
Amaurochaete fuliginosa (Sow.) Macbr.—This species appears
at all times of the year, and only on coniferous wood. Typical
black aethalia developed on a log of Scots pine in June 1909,
in a garden at Leytonstone.
Brefeldia maxima (Fries) Rost.—Not common; between the
years 1887 and 1896 this species continued to appear on certain
stumps in Wanstead Park in autumn and winter, the aethalia
forming conspicuous dark brown cushions four to eight inches
across ; it has not since been recorded from Essex."
Cribraria argillacea Pers.—Not common ; it appeared in
July 1888 and 1894 on a Spanish chestnut stump in Wanstead
Park, and has developed several times on logs of Scots pine in a
Leytonstone garden. Like most species of the genus,
C. argillacea usually occurs on coniferous wood, and in the
summer months.
C. aurantiaca Schrad.—Not common in this district ; for
several years it occurred on the same chestnut and pine wood
as the preceding species in August and September ; Mr. Ross
also obtained it near Chingford, August 1916. Two forms have
been observed, viz., one with ochraceous spores and large or
small flat nodes to the sporangial net, the other with golden
yellow spores and usually dark rounded convex nodes to the net.
C. rufa (Roth.) Rost.—One record only of this species is
known for Essex. It was found on decayed wood of a pollard
oak, about five feet from the ground, in Lords Bushes, Buckhurst
Hill, October 1915. This is the one instance I know of the
sporangia occurring on any but coniferous wood. They are
weakly developed, the net enclosing the upper part of the
sporangium, instead of consisting of narrow firm threads, as in
typical specimens, is represented by membranous extensions
15 A large growth has again appeared in Wanstead Park in the summer of 1917.