688 TRANSACTIONS OF SECTION K, 
An antheridium is usually developed ; when present it either becomes continuous 
with the trichogyne or degenerates before reaching this stage. 
We were not able to trace the breaking down of the wall between the trichogyne 
and ascogonium, but we think it probable that normal fertilisation sometimes takes 
place. In the absence of this process we infer that a form of reduced fertilisation 
occurs, similar to that observed by one of us in Lachnea stercorea. 
After fertilisation or its equivalent has taken place, sheathing hyphe grow 
around the archicarp, arising mainly from the cells of the stalk. They eventually 
form two layers—the outer protective, the inner nutritive. The ascogonium 
becomes septate and its cells branch, giving rise to ascogenous hyphe. These 
grow irregularly among the nutritive cells and produce asci. The nuclei of the 
ascogenous hyphee are often in pairs. Fusion of two nuclei occurs in the ascus. 
This is followed by three karyokinetic divisions, and eight spores are produced. 
Pairs of confluent ascocarps were occasionally seen. 
Recent observations on Eremascus (Stoppel, 1907) have brought into renewed 
prominence the question of the phylogeny of the Ascomycetes. The genus 
Aspergillus is no doubt primitive; its antheridium and archicarp (still more, 
perhaps, those of Penicillium) recall the ‘copulating hyphe’ of Eremascus. In 
another direction it may be related to Boudiera, the paired ascocarps forming a 
possible step towards the compound arrangement normal in that genus. Recent 
work (Claussen, 1907) has approximated Boudiera and Pyronema. The spermatia 
and the septate archicarps of the Lichens and Pyrenomycetes may also be related 
to the sexual organs of Aspergillus. In this genus, as in Spherotheca, the 
antheridium develops as a hypha, at the end of which an antheridial cell is cut off. 
If this cell, instead of fusing with a neighbouring archicarp, were set free from its 
parent hypha it would scarcely differ froma spermatium. In Nemalion (Wolfe, 
1904), among the Red Algz, the so-called spermatium is actually an antheridium, 
and still contains two nuclei. 
2. Fertilisation in Ascobolus furfuraceus (Pers.). By E. J. WELSFORD. 
The development of Ascobolus furfuraceus was first described in 1871 by 
Janczewski, and since then has been more fully investigated by Harper and by 
Dangeard., 
The ascocarp in its early stages consists of a scolecite of from six to ten cells, 
arising from a dense tangle of multinucleate hyphe, and is rapidly covered by a 
hyphal sheath, The cells of the scolecite are at first uninucleate, but they soon 
increase in size and become multinucleate; one of them, generally that fourth 
from the apex, is larger than the others, and gives rise to the ascogenous 
branches. Large circular pores are present in the transverse walls of the scole- 
cite, and through these the nuclei and cytoplasm of the neighbouring cells 
migrate into the large cell, Here they fuse in pairs, and the fusion nuclei 
eventually pass into the ascogenous hyphx, which by this time have grown out 
from all parts of the ascogenous cell. Asci arise as branches of these hyphe and 
the ascogenous cell is soon emptied of its contents. 
The process of syngamy in Ascobolus furfuraceus is evidently of a reduced 
type, since a male organ is not present. Fusion in pairs of the nuclei of the 
scolecite, however, takes place. ‘The ascogenous cell in which this occurs is 
obviously female. If the neighbouring cells of the scolecite be placed in the same 
category, the sexual fusion in Ascobolus furfuraceus closely resembles that in 
Humaria granulata ; if, on the other hand, tuese supernumerary cells be regarded 
as vegetative, the form of syngamy approximates to that observed in such of the 
Uredinese as Phragmidium violaceum. 
3. Nuclear Fusions and Reductions in the Asconvycetes. 
By Miss H. C, I. Fraser. 
The following observations were made primarily on Humaria rutilans, a small 
orange Discomycete with exceptionally large nuclei. 
