486 



SCIENCE. 



[X. S. Vol. XXI. Xo. 535. 



of saccharose, (7) reduction of nitrates, 

 and (8) chromogenesis. 



Any combination of the above-named 

 characters gives a character complex which 

 can be best represented by a series of 

 digits. Each digit represents a character 

 in order of value. When the character 

 covered by a digit is either positive or neg- 

 ative two numbers only are necessary, i. e., 



1 and 2, 1 signifying positive and 2 nega- 

 tive. Thus spore formation and non-spore 

 formation by 1 and 2 in the hundreds 

 place 5 aerobic-facultative anaerobic and 

 anaerobic by 1 and 2 in the tens place, and 

 liquefaction and non-liquefaction of gelatin 

 in the units place represented by 1 and 2. 

 In the tenths, hundredtlis and thousandths 

 place of decimals three munbers are used, 

 in which 1 represents acid with gas and 



2 acid without gas, while 3 no acid from 

 dextrose, lactose and saccharose respect- 

 ively, 1 and 2 in the next place indicate 

 reduction and non-reduction of nitrates, 

 and in the next place numbers from to 

 8 indicate the absence or the presence of 

 chromogenesis in the order of the occur- 

 rence of the colors in the spectram, namely, 

 0, non-chromogenic ; 1, fluorescence ; 2, 

 violet; 3, blue; 4, green; 5, yellow^; 6, 

 orange ; 7, red ; 8, brown ; on this basis the 

 number for B. colt is 212.11110, for B. 

 enteritidis 212.13310. 



A Revision of the Coccaccce: C.-E. A. 

 WiNSLOW and Anne F. Rogers, Massa- 

 chusetts Institute of Technology. 

 Since the swamping of minor differences 

 by sexual reproduction is absent among 

 bacteria, every inheritable variation is 

 maintained, and instead of ti"ue species we 

 find an infinite series of minutely differing 

 but constant races. The only practical 

 method of handling and systematizing 

 these is to establish certain fairly distinct 

 groups or types about which the lesser in- 

 dividual variations may be grouped. The 



larger number of published descriptions of 

 species among the cocci are based either on 

 variable or on isolated and unimportant 

 characters. The authors find that 445 de- 

 scribed species may be condensed to 31. 

 These are grouped under two subfamilies 

 and five genera which mark transition 

 stages between strictly parasitic pairs of 

 cells like D. WeichseJbaumii and strictly 

 saprophytic organisms in large vegetative 

 masses like Ascococcus mesenteroides. The 

 principal groups are defined as follows : 



FAMILY COCCACE^. 



Vegetative cells spherical. 

 Subfamily I. Paracoccace^ (new sub- 

 family). 



Parasites (thriving only or best on or in 

 the animal body). Thrive well under 

 anaerobic conditions. Many forms fail to 

 grow on artificial media, none produces 

 abundant surface growth. Planes of fis- 

 sion generally parallel producing pairs or 

 short or long chains. 

 Genus 1. Diplococcits ( Weichselbaum). 



Strict parasites. Not growing or grow- 

 ing veiy poorly, on artificial media. Cells 

 normally in paii-s, surrounded by a capsule. 

 Genus 2. Streptococcus (Billroth). 



Parasites. Cells normally in short or 

 long chains (under unfavorable cultural 

 conditions, sometimes in pairs and small 

 groups, never in large groups or packets). 

 On agar streak, effused translucent growth 

 often with isolated colonies. In stab cul- 

 ture, little surface growth. Ferment 

 sugars with formation of acid. 



Subfamily II. j\Ietacoccace.e (new sub- 

 family). 



Facultative parasites or saprophytes. 

 Thrive best under aerobic conditions. 

 Grow well on artificial media, producing 

 abundant surface growths. Planes of 

 fission often at right angles; cells aggre- 

 gated in groups, packets or zooglea masses. 

 Genus 3. Micrococcus (Ilallier) Cohn. 



