378 Kauffman . — A Contribution to the 
equilibrium, has occurred at the point where the antheridial filament 
originates. 
In this connexion attention should be called to Figs. 17 and 18, which 
show a condition apparently seen in part by Klebs (’99, p. 566). Here the 
antheridial filaments, poorly developed on the oogonium of Fig. 17, but 
with well- developed antheridia in Fig. 18, grow profusely around the 
oogonia. In all these cases, however, the oospheres seldom mature, but dis- 
integrate as if absorbed. Klebs indeed states that antheridia-like filaments 
form in profusion, but, in his opinion, instead of fertilizing the oospheres, 
consume them. From his brief statement it seems that he did not observe 
definite antheridia at the apices of the filaments in his .S. mixta . As shown 
in my figure, these are very abundant and definite in such cultures of 
vS. hypogyna. That these are true antheridial branches is shown by these 
antheridia at the apices as well as by the presence of intermediate forms 
where the short side-branch has developed to a greater or less extent in the 
direction of the extreme stage. They are mostly without fertilizing tubes 
and lie only on the surface of the oogonium ; the figure lacks perspective, 
and the antheridia, which seem to have penetrated the oogonial wall, lie on 
its hither surface. The idea that the antheridia devour the contents of the 
oogonium is hardly applicable in this case ; and yet there seems to be 
a close connexion between the disintegrating process and the presence 
of many antheridia. In Fig. 17 two oospores were formed before the 
blighting effect of the male filaments reached them, while the remaining 
oospheres disintegrate. It may be that this phenomenon is explicable 
in another way than by assuming a direct evil effect due to contact of 
antheridial filaments, viz. that the nutrition the plant as a whole is directing 
into these filaments is taken from the amount which would normally supply 
the oogonial filaments, and hence the latter are famished. There is, how- 
ever, the difficulty that one finds in the same cultures with these extreme 
forms, oogonia with male branches well developed, and which have the 
normal structure as in Fig. 16. 
As already stated, not only was the effect of phosphates very marked, 
but also that of nitrates, and even potassium sulphate and magnesium sul- 
phate showed a favourable increase in the number of oogonia as well as of 
antheridia. To test the stimulative effect of salts whose nutritive value 
is known to be of no importance in certain other fungi, sodium chloride was 
added to a number of haemoglobin solutions along with potassium phos- 
phate, and compared with those containing phosphate and haemoglobin 
only. There was a decided improvement in the appearance of the oogonia, 
as well as in the number of antheridia formed. Fig. 18 was drawn from an 
example of such a culture. A set of cultures with potassium sulphate added 
to the other ingredients seemed also to have a favourable effect, perhaps 
neutralizing the disintegrating effect of K 3 P0 4 , and allowing the oogonia 
