On two species of Heterosporhim particularly Heterosporium echinulatum 
3 
the description is a drawing showing a bundle of conidiophores, but 
the articulations between the conidia and their conidia-bearing-hyphae 
are not indicated. The conidiophores were moreover asserted to be 
colourless and the dimensions were given in inches. In 1873 Berkeley 
and Broome renamed it Helminthosporium exasperatum and added a 
fairly good although short description of the conidiophore. They state 
that the .,Flocci (are) knotted above, each knot bearing an oblong spore.“ 
The figures also show the articulations on the heads of the spore-bearing- 
hyphae and upon the spores. 
In 1876 Cooke placed the Fungus in a new genus, namely Hetero¬ 
sporium, and called it H. echinulatum; he gave no figures, but the 
dimensions of the spores are given in millimetres and are as follows 
0,3—0,5 mm x 0,1—0,125 mm. 
In 1881 it was referred to by Saccardo and Roumigier as 
H . Dianthi. Magnus gave an account of the carnation disease in 1888. 
In 1888 Rostrup published an account of the disease of carnations 
due to H. echinulatum with two figures, one of a Dianthus branch with 
disease spots upon the leaves, the other of conidiophores of the parasite. 
All these accounts deal only with the outward appearance of the 
disease upon the carnation leaves, and the figures of the conidiophores 
are evidently from material scraped off from the disease spots. 
Schroeter gave a good but short description of the parasite under 
the name of H. echinulatum in 1893, and gave the correct dimensions 
and colour of the conidia. It was again described by Sorauer in 1898. 
Neither Bailey, Duggar, nor Farlow and Seymour mention 
H. echinulatum as parasitic upon carnations in North America. 
2. The species of Heterosporium upon Beta. 
Some difficulty was experienced in assigning a systematic position 
to the form described here as Heterosporium Betae. At first it was 
considered to he a species of Cladosporium', on closer observation, however, 
the conidia and conidia-bearing-hyphae were found not to agree exactly 
with the figures given for Cladosporium (see Janczewski on Cladosporium 
herbarum, and Schostakowitsch on the same); but corresponded almost 
exactly with those of the conidia and conidiophores of H. Syringae, 
Klebahn 1 ). The variability in the length of the spores (20 /a — 13 ja ), 
their shape which was cylindrical with rounded ends, and not oval as are 
those of Cladosporium , together with the fact that the heads of the 
conidia-bearing-hyphae and of their prolongations are decidedly swollen 
spherical structures (fig. 11), which is not the case in Cladosporium , 
decided the genus of this fungus as Heterosporium and not Cladosporium. 
The dimensions of the conidia bring it near to such forms as H. Hordei 
Bubak, H Phragmitis Sacc., H. proteus Starb., PL Laburni Oudem., 
H Beckii Bäuml. None of these, however, occur on Beta , nor indeed 
has any Heterosporium been before recorded as growing upon this host. 
It was not found possible to identify it with any of these forms, nor in 
fact to say with certainty that it is not identical with any one of them, 
because of the shortness of the descriptions and of the very small diffe- 
1) Klebahn, Krankheiten des Flieders, p. 11. 
