Presidential Address. T. Petch. 31 
he cited in support of it are not correct. Aschersonia oxyspora 
Berk. is an Aschersonia, and its Hypocrella stage was unknown 
until recently collected in Ceylon. In Aschersonia taitensts, the 
stromata are not covered with spores; they bear discontinuous 
spore masses which have oozed out of the pycnidia, and the 
supposed primordia of the perithecia are the pycnidia in which 
they were produced. Moreover, no case is known in which the 
pycnidial form is followed by the development of an ascigerous 
form on dead fallen leaves. When the leaf falls, the fungus 
decays. 
In general, an Aschersonia stroma does not subsequently 
become perithecial. Exceptions to that rule may be found in 
Aschersonia turbinata and Aschersonia placenta. But effete 
Aschersonia stromata usually decay, even when on living leaves, 
or stems. In some gatherings, all the stromata will be A scher- 
sonia, in others all Hypocrella, and it has not yet been possible 
to determine what conditions govern the production of either 
stage. Just as, in Sphaerostilbe, the Microcera stage iscommoner 
than the Nectria stage, so the Aschersonia stage is much more 
frequent than the Hyfocrella stage. 
How, then, is it possible to correlate species of Aschersonia 
with their Hypocrella stages? Simply by finding, as Massee 
thought he had, both stages in the same stroma. Instances do 
occur in which a stroma is, at the same time, pycnidial and 
perithecial, and one has to wait until they turn up. 
The first definite proof of Massee’s theory was provided by 
Mdller*, who found both stages in the same stroma in Hyfo- 
crella cavernosa. Moller also observed that A schersonia basicystis 
was similar in shape, etc., to Hypocrella phyllogena, and recorded 
that Lindau had found both stages in the same stroma in 
specimens sent him from Brazil. Zimmermann} described both 
stages in Hypocrella Raciborskii, and Thaxter{ has found both 
in Hypocrella turbinata, while during a recent revision of these 
two genera, both stages have been found in the same stroma 
in the case of eleven other species. 
As I have already stated, 70 species of Hypocrella and 
60 species of Aschersonia have been described. In revising 
these genera, it has been necessary to make seven new species 
and to transfer four from other genera. Nevertheless, the total 
number of valid names is only 54, covering 42 species. In the 
group parasitic on Lecanium, there are at present, 20 species 
of Hypocrella; the corresponding A schersonia is known in eleven 
cases, and in six of these it has received a name. In the group 
parasitic on Aleyrodes, there are nine species of Hypocrella; the 
* Phycomyceten und Ascomyceten, 1got. t Op. ctt., subra. 
$ Botanical Gazette, Lvi1, pp. 308-313. 
