12 KANSAS UNIVERSITY SCIENCE BULLETIN. 



and after a few days an examination of the new race showed 

 the characteristic elongated form. 



The peculiarities of the new race are such that tliey can be 

 better understood by reference to the illustrations than by 

 statistics. However, in order to get some exact data regard- 

 ing the elongated character of the cells, I obtained the ratio 

 between the length and breadth of 272 cells of the new race 

 and 212 of the check. In all but 70, measurements were 

 taken of the living cells, in order to avoid error due to shrink- 

 ing in fixation and staining. Measurements were in nearly 

 all cases made with a yV oil-immersion objective or with a 

 Zeiss F, and with the micrometer scale in a one-inch ocular. 

 Cells from ten different cultures were taken, with one excep- 

 tion all from glucose broth cultures in hanging drops or from 

 test-tubes. In each of the ten cases, with one exception, the 

 check was of the same age as the new race and grown under 

 the same conditions. Much elongated, filament like cells 

 were not included in the estimate, and for the most part cells 

 were chosen in which the size or the presence of a well- 

 developed bud showed maturity. Ratios were calculated for 

 each cell separately and the average taken of these ratios. 

 The average ratio of length to breadth was in the check (212 

 cells) 1.190 to 1.000; in the new race (272 cells), 1.441 to 

 1.000. 



New races of the type described above are characterized by 

 a partial loss of the power to produce spores. Many attempts 

 were made to secure abundant spore formation, among them 

 cultivation on potato, on agar of various sorts, and in shallow 

 hanging drops of various liquid media. Actively growing 

 cultures were also placed on gypsum blocks, moist filter-pa- 

 per, and on a moist sponge. A considerable range of tempera- 

 ture was employed. 



Spores were obtained abundantly in shallow hanging drops 

 in one or two cases, and on glucose agar ; but in most of the 

 experiments spores were obtained in relatively small num- 

 bers. In all successful spore cultures, with the possible ex- 

 ception of one on glucose agar, there were fewer spores formed 

 in the new races than in the check ; and in some instances, 

 where considerable numbers were formed in the check, there 



