GENERAL SYSTEMATIC BACTERIOLOGY 331 



Homococcaceae. A subfamily of the family Coccaceae created by 

 Fischer (1897, p. 32) to include those cocci in which the planes of 

 fission are in a definite sequence. The following genera were included, 

 Sarcina, Planosarcina, Pediococcus and Streptococcus. 



The same name was also used by Fischer in 1903, p. 59. 



It should be noted that the name is not derived from one of the 

 constituent genera. 



Hyalococcus. A generic name proposed by Schroeter (1886, p. 

 152) with the following generic description: 



Zellen kugelig oder elliptisch, einzeln oder zu 2, seltener in Reihen zu 4 und 6 in 

 einfache, weit abstehende, scharf umgrenzte Kapseln eingeschlossen. Two species 

 were included, H. pneumoniae (the pneumococcus of Friedlander) and H. Beigelii. 



Hansgirg (1888, p. 266) included this as the fifth genus of his sub- 

 family Cystococcaceae. It was listed as a sjoionym of Chlamydatomus 

 by De Toni and Trevisan (1889). It was recognized by Ludwig 

 (1892). 



The name was rejected by Erwin F. Smith (1905) and by Vuillemin 

 (1913, p. 521). 



The fact that Hyalococcus pneumoniae is given first would seem to 

 fix it as the type. It is the pneumobacillus of Friedlander (not Fraen- 

 kel's pneumococcus). It would seem that this is a valid generic 

 designation for this group of organisms, in spite of its inappropriateness, 

 providing they are worthy of generic recognition. It would seem 

 to have priority over Encapsulatus q.v. which has the same type species. 



Hydrogenomonas. A generic name proposed by Orla-Jensen (1909, 

 p. 311) in the following paragraph: 



Die Oxj'dation des Wasserstoffes: 



H2+ = H20 + 69 Kal. Per Gramm 3.83 Kal. 



Nach Kaserer wird dieser Prozesz von einigen monotrichen Kurzstabchen 

 ausgeflihrt, die von ausschb'eszlich anorganischer Nahrung leben konnen, jedoch 

 auch auf organischem Substrat gedeihen, weshalb er sie Bacillus pantotrophus 

 genannt hat. Xach B. Niklewski wiiehst dieser Organismus nur im Verein mit 

 anderen Bakterien autotroph. Nach meiner Xomenklatur kann man ihm passend 

 den Gattungsnamen Hydrogenomonas geben. 



It is included as the third genus of his famil}'- Oxydohacieriaceae. 

 Niklewski (1910, p. 113) accepted this generic designation and 

 named two species, H. vitrea and H. flava. 



