Some Suggestions as to the Phylogeny of the Ascomycetes 
153 
etc. In the other direction there was a further development of the 
apothecial type resulting in the typical Pezizales, Helvellales etc. By 
reduction, such forms as Exoascus arose from this type. 
In some of these lines of development the formation of a separate 
antherid was gradually omitted, the sexual fusions taking place now bet¬ 
ween nuclei all of which originated within the carpogone. 
I can not refrain at this point from urging the strict homology 
between the ascus, and the teliospore of the Uredinales. In both cases 
a union of two cells gives rise to one or several, ascogenous filaments, 
within which the cells are binucleate. At or near the end of such a 
filament cells arise within which the two nuclei unite, forming the young 
ascus or teliospore as the case may be. In this cell now begins the 
reduction division, leading to the production within the ascus of four 
or mostly eight ascospores, and in the teliospore (in some Uredinales) 
or in an outgrowth from it (promycelium), of four cells which may form 
germ tubes directly but usually form secondary spores, the so-called spo- 
ridia or basidiospores. By the same token the spores of the Ustilagi- 
nales and even the basidia of the Basidiomycetes are perhaps homologous 
to the ascus, and these groups, too, are probably derived from the Asco¬ 
mycetes. 
Protascus eolorans, a new genus and a new 
species of the Protoaseineae-g roup; the source 
of “Yellow-grains“ in Rice. 
By 
P. c. VAN DER WOLK, Buitenzorg (Java). 
(With 1 col. plate.) 
1. Introduction. 
One of the most fearful calamities in the trade-rice of some coun¬ 
tries, viz: — the rice which is exported from the Indies to the European 
market for consumption — is the appearance of the so-called “yellow grains“. 
If a handful of rice be taken out of such an infected lot then “yellow 
grains“ immediately come into view here and there. It is the endosperm 
that looks yellow. Now, it is no usual yellow colour that these same 
grains exhibit; the colour inclines a little to be brownish; so, one is more 
disposed to speak of brownish-yellow grains; sometimes there is an over- 
lying deep orange glow. In all cases the grains are of a deep-yellow 
colour, a yellow fonce, so that one may without doubt speak of “yellow grains“. 
This phenomenon of “yellow grains“ is not a matter of general 
spreading; but in the countries where it is endemic, it is in the highest 
degree dreaded by the rice-producers. Rice which has only just been 
harvested does not immediately exhibit yellow grains. They only appear 
in rice which has been garnered for a long time in large heaps. The 
yellow-colouring process progresses very slowly. It is not until after 
several months have elapsed that one has the chance of finding yellow 
