1921] BLAKESLEE, CARTLEDGE, & WELCH—CUNNINGHAMELLA 1099 
gross cultures to obtain the races to be investigated, as well as the 
detailed methods of making contrasts between them has been 
described in a previous publication (12) and need not be repeated 
here. Table III gives the origin of the different races used in 
the tests. Samples of different types of soil were taken from 
different stations, chiefly near Cold Spring Harbor, and were the 
source of races of C. elegans and C. echinulata. Brazil nuts fur- 
nished both C. bertholletiae and C. echinulata, as well as the undeter- 
mined species A. All the gross cultures were given a serial number 
preceded by the letter JT or H. The individual nuts in these 
cultures were indicated by capital letters, and the same was done 
for the spots on the soil and bread cultures from which transfers 
were made. In some cases more than a single transfer was made 
from an individual nut, as is shown by nos. 737 and 738. Generally 
more than a single race was isolated from each gross culture which 
showed fruits of the fungus sought, since, as table III shows, 
sexually distinct races are frequently present in the same gross 
culture. Undoubtedly among our numbered races some are dupli- 
cates, but duplication would probably not have been avoided if only 
a single race had been taken from each purchased collection of nuts. 
More races of a single species were taken from 7117 than from 
any other gross culture. From this culture, however, both plus 
and minus sexes were obtained, and the various races of the same 
sex are far from all being duplicates, as may be seen by comparing 
the records of nos. 732, 733, and 739, shown in table VII A. 
Despite the facts that the opposite sexes were frequently found to 
be present in the same culture and that the gross cultures were 
run at a temperature favorable for sexual reproduction, no zygo- 
spores of Cunninghamella in gross culture were found. Their 
absence may be due to the relatively meager growth of the fungus 
under the conditions in gross cultures. 
The tests with the different species may be considered sepa- 
rately. The individual and mean grades were assigned as already 
described (10, 12). For the most part, individual contrasts were 
made only once, since it seemed more profitable to obtain some- 
what roughly graded records of a relatively large number of separate 
