hypocrella and aschersonia. 197 



Systematic Accoitnt. 



The species of Aschersonia may be arranged in two groups, 

 according to the presence or absence of paraphyses. And 

 this feature, as far as the species hitherto known indicate, 

 is correlated with the kind of insect on which the fungus is 

 parasitic. Species parasitic on AUyrodidae have paraphyses; 

 those parasitic on Lecaniidss do not. It is proposed to take 

 these two groups as subgenera, under the names of Eu- 

 Aschersonia and Leprieuria respectively. Eu- Aschersonia 

 has been selected for the Aleyrodiicolous group, because the 

 type species of the genus Aschersonia, A. taitensis Mont., 

 possesses paraphyses. 



The difference between the corresponding species of Hypo- 

 crella is not so easily defined. The Lecaniicolous group have, 

 in general, harder, more compact stromata than the Aleyrodii- 

 colae. The stromata of the first group are usually hemispheri- 

 cal, two-thirds globose or scutate, while those of the second 

 are. discoid or irregularly' flattened pulvinate. The two stages 

 are found in the same stroma, more frequently in the LecaniicoUs 

 than in the Aleyrodiicolse . The type species of the genus 

 Hypocrella, Hypocrella discoidea, is an Aleyrodiicolous species, 

 and the Aleyrodiicolse may, therefore, be known as Eu- 

 Hypocrella. For the harder species of the Lecaniicolse the 

 generic name Fleischeria has been proposed by Penzig and 

 Saccardo. Wliile it is not possible to consider hardness as a 

 generic character, the name, as applied by Penzig and Saccardo, 

 denotes a species which differs from Eu- Hypocrella in its 

 pycnidial stage by the absence of paraphyses. It is proposed, 

 therefore, to employ the name Fleischeria as a subgenus for 

 the species parasitic on Lecaniidae. 



List of Species. 



As will be evident from the following list, the Hypocrella 

 stage of all the known species of Aschersonia of the group 

 Lecaniicolse has been determined ; their descriptions have 

 consequently been included with the related Hypocrella. 

 On the other hand, the Hypocrella stage is known in less than 

 half the Aleyrodiicolous species of Aschersonia. 



