32 Transactions British Mycological Society. 
Aschersonia stage of each of these is known, and in six cases it 
has been named, while there are in addition 13 unattached 
Aschersonias. 
Hypocrella and Aschersonia occur on living leaves and stems, 
on which they form superficial, easily detached stromata. The 
stromata are usually brightly coloured—white, yellow, red, or 
brown—and may be subglobose, hemispherical, flattened pul- 
vinate, or scutate. As a rule, they do not exceed 3 mm. in 
diameter, but one giant from Brazil, Hypocrella Gartneriana, is 
said to attain a diameter of 3cm. The stroma is composed of 
thick-walled hyphae and in the species parasitic on Lecanium 
it is usually very hard and sclerotioid. Penzig and Saccardo* 
instituted the genus Fleischeria for the harder species of Hypo- 
crella, and, while it is scarcely possible to consider hardness 
a generic distinction, the name can be associated with a morpho- 
logical character, as it was applied to a Hypocrella, whose 
Aschersonia stage has no paraphyses, whereas in the type species 
of the genus Hypocrella, the Aschersoma stage has paraphyses. 
This sclerotioid character is no doubt to be correlated with the 
fact that these fungi are superficial, and, not being able to 
obtain water from the leaf, must be able to withstand periods 
of drought. It is shared by several other fungi in the tropics 
which overrun leaves and twigs: the common Thread Blights, 
for example—white, normal-looking mycelia which occur on the 
upper parts of bushes and trees—are composed chiefly of 
sclerotioid hyphae. 
One peculiar species, Hypocrella scutata, which has been found 
in Singapore and the Philippines, has a stroma composed chiefly 
of resin in which the hyphae are embedded. It breaks with a 
vitreous fracture, and if a lighted match is applied to it it burns 
like resin. Failing any other explanation, one is led to assume 
that this peculiarity is due to the insect on which it is parasitic, 
but it has not been possible to verify that assumption. 
In all the collections of Hypocrella and Aschersonia which I 
have examined, whenever it has been possible to identify the 
insect, the latter has belonged to the Lecantidae or to the 
Aleyrodidae. Aschersonia Coffeae has been recorded} as occurring 
on Asfidiotus, and Aschersonia marginata on Parlatoria, but 
these records are probably erroneous. It is necessary to exercise 
great caution in deciding what insect a Hyfocrella is parasitic 
upon. If a Lecaniuwm and a Lepidosaphes occur together on the 
same leaf, a lecaniicolous Hypocrella may destroy all the indi- 
viduals of the Lecanium, leaving only the Lepidosaphes. 
Another ascigerous genus, which occurs on scale insects 
* Malpighia (1901), p. 230. 
t+ Journ. Coll. Agric., Tohuku Imp. Univ., Sapporo, v (1913), pp. 73-90. 
