TAXONOMIC CHARACTERS OF ALTERNARIA AND MACROSPORIUM 47 1 
M. tenuis simum (Nees) Fries becomes the type of the genus Macro- 
wSporium, which will take over the species now given under* the genus 
Clasterosporium, Clasterosporium being antedated by Macrosporium. 
All but twenty of the species of Macrosporium listed in the "Syl- 
loge Fungorum" belong to Alternaria. These twenty are given as 
having globular and sarcinaeform, or globular and clavate spores. 
The latter species may possibly have both forms of spores but it is 
much more probable that in most cases the "clavate" spores belong to 
Alternaria and that two distinct forms were present when the species 
were described. Such mixtures were found in the exsiccati in several 
instances. Of the two species studied in culture M. sarcinula very 
rarely produced a pointed spore bearing another spore and might be 
considered a bridging species to Alternaria. 
All of the twenty species given in the ''Sylloge Fungorum" having 
sarcinaeform or globose spores are one species in so far as spore meas- 
urements are dependable. Of the thirteen specimens found in ex- 
siccati, however, there were two distinct forms, and two distinct forms 
were cultured during the present studies. Some of the names of the 
twenty species in question have already been reduced to synonymy 
and it is probable that only a few separable forms exist. 
There is nothing in the morphology of the species of this group 
which would exclude them from the genus Stemphylium. 
The species now named Macrosporium which should be put into 
Stemphylium, providing they are distinct species, are: M. sarcinula 
Berk, M. sarcinaeforme Cav., ikf. abruptum C. & E., M. haccatum Ell. 
& Kell., M. valerianellae Roum., M. elegantis simum Rabh., M. pelar- 
gonii E. & E., M. globuliferum Vestergr., M. toruloides E. & E., 
M. nodipes Sacc, M. schemnitziense BaumeL, M. puccinioides E. & 
And., M. chartarum Pk., ikf. myrmecophilum (Fr.) Sacc, M. nitens 
(Fr.) Sacc, M. suhglosum Cke. & Rav., M. rosarium Penz., M. septo- 
sporum Rabh., M. atrichum C. & E., M. parasiticum Thum., M. 
commune Rabh. 
VII. SPECIFIC LIMITATIONS OF ALTERNARIA 
Except for the species named above as belonging to Stemphylium, 
all the species of Macrosporium in the "Sylloge Fungorum" belong to 
Alternaria, and can be recognized as Alternaria from their descriptions. 
In the present studies enough variation due to age alone occurred 
in Alternaria tenuis, A. fasciculata, and A. dianthi, to fit these to a 
