368 GENERAL SYSTEMATIC BACTERIOLOGY 



cell. A truncated spindle-shaped organism, always single, 10 to 25^ long by 5/* 

 wide. Nonmotile. Cytoplasm condensed into chromatic masses, from which 

 the spores develop, which (when limited to 2) are usually bipolar. The vegeta- 

 tive forms have never been observed to divide. Nonpathogenic. 



Metacoccaceae. A subfamily of the family Coccaceae proposed by 

 Winslov/ and Rogers (1605, p. 669) to include the genera Micrococcus, 

 Sarcina and Rhodococcus. The diagnosis given is: 



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 aggregated in groups, packets or zoogloea 

 masses. 



In later descriptions (1906, p. 485, 1908, p. 258) the Winslows have 

 added: "Generally decolorize by Gram. Pigment yellow or red." 



It was pointed out by Buchanan (1915, p. 9) that the name Meta- 

 coccaceae fails to conform to the rules of botanical nom.enclature in 

 that it does not carry the right ending and is not formed from the 

 name of one of the constituent genera. Possibly this name should 

 be replaced by the tribal designation Micrococceae used by Trevisan. 



Metacoccus. A name stated by Conn (1909, p. 12) to have been 

 recognized in "recent classification of the spherical forms." The 

 writer has been unable to find the classification to which Conn refers. 

 It may be regarded as a nomen nudum. 



Metallacter. A generic name proposed by Perty (1852, p. 180) 

 for a rod shaped bacterium occurring in filaments or chains The 

 type was M. Bacillus, the Vibrio Bacillus of Milller and of Ehrenberg. 

 The name was used as a synonym of V. Bacillus Miiller by Raben- 

 horst (1865, p. 72). 



Concerning Perty's organism, Cohn (1875, p. 188) has the following 

 statement: 



Perty hatte, wie ich erst nachtraglich erfahren, unsere Bacillusarten schon im 

 Jahre 1852 als eine selbstjindige Gattung von den eigentlichen Bac+erien unter 

 dem Namen Metallacter abgetrennt (von einem griechischen Worte, welches sich 

 "venindernd" bedeutet), well dieselben in steife oder wenig biegsame, unbeweg- 

 liche, ungemein verlangerte Hygrocrocis (oder Leptothrix) — faden unter gewissen 

 Umstanden sich umwandeln; und ebenso hatte er ausserst kleine, bewegliche 

 cylindrische Faden beobachtet, welche an einem, oder seltener an beiden Enden 

 eine, manchmal auch zwei elliptische Korperchen (wohl Sporen) einschliessen; 

 obwohl er dieselben ofters mit Bacillus {Metallacter Bacillus Perty) zusammen 

 fand, denen sie sehr gleichen, hielt er sie doch ftir eine selbststandige Gattung 

 und Art {Sporonema gracile Perty). 



