[Crown Copyright Reserved. 
ROYAL BOTANIC GARDENS, KEW. 
BULLETIN 
MISCELLANEOUS INFORMATION. 
No. 10] (1923 
XXXVII.—THE BRITISH SPECIES OF CEUTHOSPORA 
AND CYTOSPORINA. 
W. B. Grove. 
The two form-genera named above will be considered here 
together, because they both resemble Cytospora*, especially in 
the fact that the spores can exude from the ostiole in a tendril. 
Cytosporina is separated from Cytospora mainly by the greater 
length and slightly different shape of its spores; it would, indeed, 
possibly be more logical if Cytosporina were considered merely 
as a subsection of Cytospora, were it not that its best-known 
members (and possibly all) belong to ascophorous genera 
different from those to which Cytospora belongs, viz., to Hutypa 
and Cryptosphaeri 
With regard to , Couthoopto, which is more divergent in form, 
there is a difference of opinion. Some deem the mark of the 
genus to reside in the straight, elongated-cylindrical, not sausage- 
shaped spores. But there seems to be one species, Ceuthospora 
Laurocerasi, occurring frequently on dry fallen leaves and twigs 
of Prunus Laurocerasus, which has spores as sausage-shaped as 
those typical of Cytospora, and yet this species agrees in other 
respects so closely with the type species of Ceuthospora (C. 
phacidioides) that it. seems impracticable to separate them 
generically. Greville, recognising their close affinity, figured 
them for the first time, in his Scottish Cryptogamic Flora, on 
two successive plates. I think that the best mark of Ceuthospora 
is to be found in the possession of two kinds of pycnidia, as 
described below : the cylindrical spores would then serve as a 
subsidiary mark. It is true that not quite all the British species 
are known, 80 far, to produce both kinds of pycnidia, but that 
genera. If this connection of the coelomycetous form-genera 
with fixed groups of ascophorous species should turn out, on 
* K.B., 1923, p. 1. 
z (78)20807 Wt 396—P 32 1000 12/23 : x 
