2 
W. J. Dowson, 
the work centered round the two Heterosforiums, which were obtained in 
the living state. At first a number of cultures were made upon various 
nutrient media with a view to observing the nature of the growth of 
these fungi upon different media. On looking through the literature of 
the genus Heterosporium it was found that hardly any of the existing 
figures were at all accurate, particularly those in connection with such a 
well recognised form as H. echinulatum; and that moreover nothing was 
known about the inoculation, infection, and nature of the mycelium of 
this particular parasite. It was therefore decided to go as thoroughly as 
was possible into these points. 
The work was carried out in the Botanic Institute at Hamburg, and 
I should like to express here my very sincere thanks to Prof. Klebahn 
for the permission to work under his direction in the Institute and for 
his continued advice and help during the progress of my work. My 
thanks are also due to Prof. Brick of the „Station für Pflanzen¬ 
schutz“ for very kindly affording me every opportunity of examining 
herbarium material, and also to the director of the Hygienisches In¬ 
stitut for kindly allowing me the use of microphotographie apparatus. 
Methods. 
The growth of the fungi was observed in petri-dish and hanging-drop-cultures. 
The germination of the spores and the formation of the conidiophores were observed 
in damp chambers as described by Prof. Klebahn 1 ). 
The culture media used were, 
Plum-juice agar 
Meat-extract agar (Fleischwasseragar) 
Liebigs „ „ (Fleischextractagar) 
Glucose ,, 
Maltose „ 
Salep „ 
The agar for the salep - agar medium was previously treated according to 
E. Macé 2 ). 30 gm. of this prepared agar was gently simmered for 1 / 2 hour in 1 lit. 
water (tap). 9 gm. Salep (N. Bernard) 3 ) were gradually stirred into 1 lit. tap-water 
and gently simmered for 1 / 2 hour; the two liquids were added together and made up 
to 2 lit. by the addition of tap-water. To this mixture were added the following 
(Klebahn): 
Salep agar. 1 gm. grape sugar, 
0,2 gm Monopotassium phosphate, 
trace Ammonium-nitrate, 
„ „ -sulphate, 
„ ,, -ferrous sulphate, 
,, Magnesium sulphate, 
0,2 gm. tartaric acid. 
The whole was kept gently simmering for i / 2 hour after which it was filtered 
in steam till it was quite clear and then poured into soxlet-bottles which were 
sterilised 4 ). 
The methods employed in killing and staining are described under the infection 
experiments and under the examination of the diseased tissues of Dianthus. 
1. J heterosporium echinulatum (BERKELEY) COOKE. 
The leaf-disease due to this parasite was first described by Berke¬ 
ley under the name of Helminthosporium echinalatum in 1870; with 
1 ) Pringsheims Jahrbücher, 41, 489. 
2) Traité pratique de Bactériologie, Paris 1889. 
3) Rev. gén. de Bot., 1904, 16, 408. 
4) see Himmelbauer, Jahrbuch der Hamburgischen Wissenschaftlichen An¬ 
stalten, 28, 43. 
