12 PREFACE 



number of observers have made contributions in this field, but the 

 writings are so widely scattered and, in many cases, the journals and 

 other publications so difficult of access that for the most part they are 

 quite unknown to our modern writers or, at least, unheeded by them. 

 It is believed that a synopsis of these various schemes of classification 

 that have been proposed and a comparison of the various bases upon 

 which these rest must surely be of service in developing a stable bac- 

 teriological nomenclature. 



The second chapter has to do with codes of nomenclature and their 

 relationships to the problems of bacterial terminology. The subject 

 of nomenclature is, in part, distinct from that of classification. The 

 latter deals with methods and criteria of use in the differentiation of 

 groups from each other. The former has for its function the deter- 

 mination of the kind of a name that shall be applied to a group and the 

 validity and suitability of names which have already been applied. 

 This frequent confusion of nomenclature in classification has made 

 us hesitate to give a name to that which we cannot accurately define. 

 It is true, however, that species have not been accurately delim- 

 inated in the older biological sciences, but this fact has not interfered 

 with at least tentative arrangements of the genera and higher groups 

 nor of application of correct names. It seems to be self-evident that 

 until the bacteriologists can agree upon a code and follow it consist- 

 ently, there is little hope or remedy for our present chaos. It is 

 believed that the discussion of the International Botanical Code given 

 in this second section will show that it may constitute an adequate 

 basis, which, with some modification, may prove satisfactory as a 

 guide. 



The third chapter is an alphabetical list of all of the names which 

 have been used by various authors to designate bacterial subgenera, 

 genera or higher groups so far as a rather comprehensive study of the 

 literature has revealed them. Wherever practicable the original de- 

 scription has been quoted, the descriptions used by various subsequent 

 writers discussed, and sufficient data included to make possible in 

 most cases, at least, the formation of an opinion as to the probable 

 nomenclatural status of each name. It is believed that this list will 

 prove helpful in the determination of the exact meaning of the various 

 names, in the formulation of adequate diagnoses for the determination 

 of synonymy, and in preventing the introduction of new names where 

 there are valid older names. 



