July 31, 1916 Life Cycles of the Bacteria 693 



large forms * are passing over into the symplastic stage. Many bright 

 gonidia, some deeply stained regenerative bodies, and a few normal slen- 

 der rods are seen. This illustration should be compared with figures 26 

 and 27 of Plate E. 



The two salt-water spirilla included in our experiments were also 

 inclined to produce symplasm, globular and irregular regenerative 

 bodies like the representatives of all other groups of bacteria. We 

 have preferred, however, to show in figures 35 and 36 (PI. F), which 

 were made from a salt-beef-agar slant only 4 hours old, some facts 

 which confirm and explain two observations made several decades ago. 

 In 1887 Sorokin (19) published a preliminary communication upon 

 his "new species" Spirillum endoparagogicum, of which, so far as we 

 know, a full description has never been given. His illustrations, repro- 

 duced in several textbooks, show clearly that he also found a budding 

 bacterium without becoming aware of this fact. That the bright 

 granules contained in the large spirilla and budding out of it, forming 

 new small rods and spirilla, were not endospores, as the author asserts, 

 seems to be beyond question. No test was made of their heat resistance, 

 and in our opinion the fact that many of them were produced in the 

 same cell proves sufficiently that they were gonidia. Their globular form 

 is also much more in agreement with this opinion than with the assump- 

 tion that the}- were endospores. Figure 35 (PI. F) shows the same 

 budding of our salt-water spirillum. Many of the irregular "involution " 

 forms, so frequently observed with other spirilla, belong also to this type 

 of growth. Furthermore, in figure 35 (PL F) , as well as in figure 36 (PI. F) , 

 several round regenerative bodies are reproduced, some of them being 

 in the germinating stage. They are either dark-stained like those of 

 other bacteria or they remain unstained when treated with aqueous 

 anilin dyes. If such unstained forms are budding out of the end of a 

 spirillum, as can be seen in the center and at the right side of figure 35 

 (PI. F), we have apparently before us the same occurrence which was 

 described by Prazmowski in 1880 (17, p. 43). We have not yet tested 

 the heat resistance of these bodies. It is possible that they are parallel 

 forms of the exospores found in the spore-forming L type of B. azoto- 

 bactcr. In the meantime they may be registered as unstained regenera- 

 tive bodies. Some different types of germination are exhibited by the 

 three regenerative bodies in figure 36 (PI. F). The lower right part of 

 figure 35 (Pi. F) contains several spirilla which may be in the conjunct 

 stage. They are wound closely around each other, forming apparently 

 one thick cell, only the end parts being separated. An analogous occur- 

 rence with Spirochaeta obermeieri has been recently observed by Levy 



1 They have been called "bacteroids" by Brunehorst because this author conceived the wrong idea that 

 they were not bacteria, but cell products looking somewhat like bacteria. We are unable to understand 

 how such an entirely incorrect term can still be used in modern scientific publications. 



