) 
Contributions to the Cytology of Helvetia 
crispa, Fries. 
BY 
D. CARRUTHERS, B.Sc. 
With Plates XVIII and XIX. 
JLTEL VELLA CRISPA , Fries, is a pale buff Ascomycete with a stalked 
ascophore, the head of which is much convoluted. Material was 
collected in the autumn of 3909 and was fixed in Flemming’s fluid, the 
strong solution diluted with an equal quantity of water being most satis- 
factory. 
Sections were cut from 3-8 ^ in thickness, and were stained with 
Flemming’s triple stain, or with Heidenhain’s iron-haematoxylin, and 
in the latter case either erythrosin or lichtgrun was used as a counter-stain. 
The research was carried out at Birkbeck College, and I wish to 
express my thanks to Dr. Fraser, at whose suggestion the work was under- 
taken, for valuable help and advice throughout its progress. 
Vegetative Tissue. 
The hypothecium is made up of a number of septate hyphae forming 
a loose tangle, the cells of which contain fairly abundant protoplasm and 
one, two, or several nuclei each. These nuclei are small ; the chromatin 
appears to be scattered in small granules round the periphery without any 
definite reticular arrangement. 
Certain of these nuclei were observed to fuse in pairs (PI. XVIII, 
Figs. 1, 2), but no evidence of migration such as has been recorded in 
Humaria ( 7 ) and in N ephrodium (6) was obtained. In most cases the cells 
of the paraphyses are binucleate, while those of the fertile hyphae have 
a larger number of nuclei, but no exact differentiation can be traced between 
the two. 
Formation of the Ascus. 
The hyphae which are to give rise to the asci are generally larger than 
the paraphyses, and have scantier and less granular contents. Their nuclei 
resemble in size and appearance the fusion nuclei of the hypothecium. 
A certain amount of evidence was obtained as to the mitoses in both 
[Annals of Botany, Vol. XXV. No. XCVII. January, 1911.] 
R 2 
