484 BOTANICAL GAZETTE [DECEMBER 
fact, when these gemmae first form, the observer is certain that 
young oogonia are being produced, but in no case have oospores 
or antheridia been observed, though hundreds of cultures have been 
examined. It is possible that in this form these gemmae are nothing 
but arrested oogonia, and that, could we find the proper conditions, 
oospores and perhaps antheridia would be developed. 
Certain details in regard to these and other tests will be pre- 
sented in another paper; at present the writer wishes to describe 
a species of Achlya, which he has named A. Klebsiana in honor of 
Professor GEoRG Kiess. The naming of this species for Professor 
K.LEBs seemed to the writer especially appropriate since at one time 
it seemed to be an exception to the rule laid down by K1Ess in 
1899 that sporangia are formed only when the food supply is quickly 
and markedly decreased. Further study, however, showed that 
this apparent exception was a real and interesting proof of the 
correctness of KLEess’s statement. The experiments showed that 
while an abundance of food was present in the solution in which 
sporangia were formed, it was not available to the growing hyphae 
and consequently might as well not have been there. While work- 
ing in Heidelberg the writer observed that a culture of A. DeBaryana 
Humphrey regularly produced sporangia in agar to which pea 
broth had been added. The sporangia were mostly borne on the 
large, vigorous hyphae that made a rapid growth immediately after 
a fresh plate of pea agar was inoculated. Later very many slender 
hyphae, which grew more slowly, were formed, and these did not 
produce sporangia. On the strong hyphae there were often 2 or 3 
sets of sporangia, but always after a time the development of 
sporangia ceased and the outer portions of the medium became 
filled with many slender hyphae. One other form which never 
produced oogonia behaved in a similar manner. The agar here 
contained an abundance of food, and yet immediately after growth 
commenced sporangia were formed; while later, when the amount 
of food present might be thought to have been decreased, no 
sporangia were formed. At that time no definite experiments were 
undertaken to explain this phenomenon. Later these cultures were 
lost, and it was not until the fall of 1913 that another form showing 
this characteristic was collected. Meanwhile, A. prolifera, A. race- 
