TRANSITION FORMS. 129 



ner-Sandoval (Dissert. Strassburg, 1898) has convinced 

 us that the true oospora varieties are much larger although 

 similarly constructed organisms, we also, with this author, 

 consider the name actinomyces (Harz) at present the 

 most correct. 



Some varieties of wide practical importance, closely 

 related to bacteria, but reminding one very strongly of 

 true algi (oscillaria), have been included under Supple- 

 ment II. 



If we cast a glance over this system, we can not deny 

 that the families and genera are often connected by tran- 

 sition varieties ; we recall only the following : The border 

 between the coccacese and bacteriacese is obliterated by 

 oval and lance-formed (!) cocci and certain extremely 

 short bacilli (compare, in the special part, Micr. meli- 

 tensis, Bacterium Fraenkelii); between streptococcus and 

 micrococcus, micrococcus and sarcina, it is often un- 

 safe to distinguish. In the cycle of growth of many 

 bacilli twisted forms occur ; flagella and endospores occur 

 in such various forms that it would lead to an entirely 

 unnatural grouping if the attempt were made to found 

 a classification that depended in part upon the flagella 

 or endospores. 



The Bacterium Fraenkelii Hashimoto, for which we are indebted to 

 the kindness of the authors, unfortunately died before we could study 

 it. Upon solid nutrient media the organism forms short rods with 

 polar flagella; upon fluid media, on the contrary, it forms quite long 

 chains of cocci and occasionally sarcina forms. Thus it connects the 

 coccaceae with the bacteriacese, as does the Micr. melitensis, and shows, 

 as we have indicated above in other examples, that sarcina forms occur 

 as growth forms in cocci and that the presence of flagella is also vari- 

 able. (See Hashimoto, Z. H. xxxi, 85. ) 



B. Systematic Description of the Most 

 Important Varieties of Fission-fungi. 



INTRODUCTORY REMARKS TO THE SYSTEM- 

 ATIC PART, ABBREVIATIONS, ETC 



1. We have described about eighty species as completely and ex- 

 haustively as possible, several hundred are briefly described, and many 

 9 



