486 BOTANICAL GAZETTE [DECEMBER 
In every case where these flasks were arranged in the afternoon 
and examined in the morning so that those on the desk would be 
unaffected by the jar caused by walking, which complicated matters 
during the daytime, it was found that sporangia had been formed 
in the flasks on the desk, that the mycelium in the flask subject to 
frequent shaking showed no sign of sporangia, but consisted of balls 
of hyphae, the whole very dense and vigorous, and that on the 
mycelium in the flasks subject to a slight jar there were many 
aborted sporangia (fig. 1). It was evident that in the latter case 
a condition of starvation had momentarily existed, stimulating the 
ends of the hyphae to the production of sporangia; that before 
these could fully develop, the slight jar of the liquid had resulted 
in a fresh supply of food being brought to the hyphae, resulting in 
renewed vegetative growth and the abortion of the partially formed 
sporangia. The formation of sporangia in the pea agar is doubtless 
to be accounted for by the slow diffusion of food in the thick 
medium. The fact that only some species behave in this way 
doubtless indicates a more vigorous metabolism on the part of such 
species; the rate of metabolism exceeds the rate of diffusion and 
the result is starvation. 
Saprolegnia Kaufmanniana has also proved interesting in that 
it shows great sensitiveness to the concentration of haemoglobin in 
solutions into which vigorous mycelia are placed. While such forms 
as S. ferax, S. mixta, or S. monoica will produce oogonia more or 
less freely in concentrations of haemoglobin varying from 0.075 to 
o.o1 per cent, S. Kaufmanniana persistently refused to respond to 
any concentration except 0.025 per cent. In this, either alone or 
with certain salts, oogonia containing oospores and accompanied 
by antheridia were regularly produced, though never in large 
numbers. 
Achlya Klebsiana, n. sp. 
This species was collected under three numbers, the plants all 
proving similar, and all were isolated as single spore cultures during 
November and December 1913. The cultures were secured from 
collections of algae from Bass Lake, near Ann Arbor, Michigan, and 
from near Coldwater, Michigan, in both cases collected by Mr. 
E. B. Matns. One culture was also secured from a dish of algae in 
