Contributions to the Cytology of Humaria rutilans, 
Fries . 1 
BY 
H. C. I. FRASER, D.Sc., F.L.S, 
Lecturer in Botany , Royal Holloway College, University of London. 
With Plates IV and V. 
U MARI A rutilans , 2 Fries [Peziza rutilans , Fries) is an orange 
^ ^ Discomycete 0*5-1 cm. in diameter, occurring in abundance on sandy • 
soil among moss. 
Material was collected during the autumn and winter of 1905 and 1906, 
and was fixed in the field, chiefly in Flemming’s weaker fluid. It was 
embedded either through chloroform or through cedar oil, and was allowed 
to remain in the bath for from half an hour to two days at a temperature 
of about 54° C. Material did not appear to be adversely affected by the 
longer time, but it cut readily after half an hour, and this period was 
employed during the latter part of the work. 
Sections were cut from 4 to 20 \x in thickness, and were stained either 
with Flemming’s triple stain or with Heidenhain’s iron Haematoxylin and 
a solution of erythrosin in clove oil. 
I have to thank Miss H. S. Chambers for valuable help in the preparation 
of material during part of the work. 
Development of the Ascocarp. 
The young ascocarp is first distinguishable as a small knot of septate 
hyphae ; sometimes one cell is larger than the others (PI. IV, Fig. 1), but 
the nuclei are quite similar, and any distinction in size is soon lost. The 
outer cells are distinguished by their rather thick walls, the inner by their 
richer protoplasmic contents (Fig. 2). 
Great difficulty was experienced in obtaining the very young stages ; 
specimens, even, in which the asci had begun to form can hardly be dis- 
1 Thesis approved for the Degree of Doctor of Science in the University of London. 
2 In naming this fungus I have followed the diagnosis given by RabenhorsPs Kryptogamenflora ; 
my specimens probably belong to the variety vivida of Nylsen. The species appears to be the same 
as that investigated by Guillermond, who, however, does not give the authority. I wish to thank 
Miss A. Lorrain Smith for her kindness in confirming my identification. 
[Annals of Botany, Vol. XXII. No. LXXXV. January, 1908.] 
