190 Transactions British Mycological Society. 
Herbarium Specimen 10. MYCOSPHAERELLA CITRULLINA (C. O. 
Sm.) Gross., on cucumber fruit collected in Florida, 1917. 
This was the perithecial stage, but no spores were ob- 
tainable from this material. 
From a study of these herbarium specimens it is apparent 
that even these do not conform with the usually accepted ideas 
of the genera Phoma, Ascochyta and Diplodina. In fact, taking 
into consideration the lack of any perithecial stage it would 
seem that the two herbarium specimens from the Ministry of 
Agriculture (No. 1 and No. 2) and those from the Kew Her- 
barium (Nos. 5, 6, and 7) should certainly not be placed in the 
genus Mycosphaerella. 
The circumstances point to the fact that, contrary to 
the usually accepted idea, the species Mycosphaerella citrullina 
(C. O. Sm.) Gross.(6) has not yet been found in England. It 
should therefore be deleted from the list of British species 
known at present. The cultural characters and general behaviour 
of authentic specimens of Mycosphaerella citrullina from 
America, do not agree with any of the fungi isolated from to- 
matoes in this country. 
Cooke’s fungus, Phoma Lycopersici, should certainly be placed 
in a different genus (Diplodina) as nearly all the spores are 
septate. 
Taking into consideration the extreme variability of the 
genera Phoma and Diplodina we have classified the forms under 
investigation in the following manner, although it is doubtful 
if a sharp line can be drawn between Series 1 and Series 2: 
Series I. 
True Phoma destructiva (Plowr.) C. O. Jamieson as defined by 
Form A, an authentic culture. 
Forms B, H and Q. 
So far in this country these forms have only been found on 
tomato fruits, although in America this fungus is able to cause 
also a disease of the leaves and stems. 
Series 2. 
Intermediate in type between Phoma and Diplodina. Septa- 
tion of spores variable, but there are always some spores septate 
and the spores are usually larger than in Group A. 
Forms E, F, J, M, P, L. 
Included in this group also are herbarium specimens I, 2, 5, 
6, 7 and 8. These forms have been found both on the fruit 
and on the stem of tomato plants. They differ considerably as 
ete pathogenicity to the stems under experimental con- 
itions. 
