SOME RECENT WORK ON MUTATION IN 

 MICRO-ORGANISMS. 



II. Mutations in Bacteria'. 

 By CLIFFORD DOBELL. 



In the following article I shall try to give a coherent summary 

 of some recent work in bacteriology in so far as it is of interest to 

 the student of genetics. This work is very extensive and scattered 

 through numerous papers dealing with medical or purely bacteriological 

 matters. It is, moreover, to some extent beyond the reach of the 

 general biologist on account of the phraseology in which it is couched. 

 I shall try, therefore, to present the facts in such a way that they may 

 be seen stripped of irrelevant detail and in language intelligible to the 

 average reader. 



Accordingly, the facts given in the following pages are to be 

 regarded as a selection from a vast array recorded by many different 

 workers, and not as a complete review of even those works given in 

 the bibliography (p. 349). They represent, rather, certain personally 

 chosen facts arranged in an orderly manner so as to interest workers 

 in genetics. It must be remembered, therefore, that many additional 

 facts — some of them perhaps of fundamental importance — are to be 

 found not only in the works to which reference is made, but also in 

 works which I have not considered*. 



I should like to point out that I employ the word "mutation" 

 throughout in the sense of Wolf (1909), who follows Baur in this 



' In a prerious article (this Journal, Vol. n. p. 201) I have given some accoant of 

 recent work on mutation in Trypanosomes. 



2 Those desiring an account of the work hitherto done on variation in bacteria, will 

 find it admirably analysed in the recent monograph by Pringsheim (1910). 



