206 DR. COHN, ON THE DEVELOPMENT OF 



Bacterium termo, Duj. ( Vibrio lineola, lilir.), represent the 

 developmental condition of a plant ; that they, are, in fact, the 

 liberated, self-motile cells (swarm-spores) of a Mycoj)hycean, 

 closely allied, morphologically, with Falmella and Tetraspora. 

 He has been unable, however, as yet to discern any motile 

 cilia in them. He proposes a new name for this form — 

 Zooglcea, with these characters. 



CeUulas minimas, bacilliformes, li3'alinai, gelatina liyalina in massas 

 mucosas globosas, uvasformes, mox membranaceas consociata;, deiu singulaj 

 elapsa3, per aqiiam vacillantes. 



Syn. Palmella Infu&ionum, Ehr. ; Micraloa teres, V. Flotow ; Bacterium 

 termo, Duj. ; Vibrio lineola, Ehr. 



The general results of his researches on the subject of the 

 Vibrionia are thus summed up. 



1. The Vibrionia all appear to belong to the vegetable kingdom, 



since tliey exhibit an immediate, close relationship with manifest 

 Alfjce. 



2. From their want of colour, and their occurrence in ^^trifying 



infusions, they belong to the group of Mycoj'M/cect. 

 o. Bacterium termo is the motile swarming form of a genus (^Zooglcea) 

 closely allied to Palmella and Tetrasjiora. 



4. Spirochcete plicatilis belongs to the genus Spirulina. 



5. The elongated, motionless vibriones ( V. bacillus, &c.) are allied to 



the more delicate forms of Beggiatoa (Oscillaria). 



6. The sliorter Vibriones and Spirilli correspond, in form and in 



their movement, with the Oscillariie and tijiindiiiw ; but no 

 definite opinion can be given as to their true nature. 



The relationship of the Oscillarise with the Vibrionia was 

 noticed even by the earliest observers. Thus O. F. Miiller 

 termed a Spirulina, Vibrio serpens; nor has the analogy 

 between them been overlooked by Ehrenberg and Perty. 



Dr. Cohn goes on to describe the great resemblance between 

 Ehrenberg's Monas prodigiosan the cause of the phenomenon 

 termed " blood in bread," and Bacterium or Zoor/laa termo. 

 The main difference between the two consisting in the shape 

 of the former, which is more spherical or ovoid than bacilli- 

 form, and its purple-red colour.* Allied with this are the 

 masses of Vibriones, which, according to Mitscherlich's 

 observation, appear on rotten potatoes, as a kind of ferment, 

 and have the power of dissolving cellulose (Monatsb. d. B. 

 Ak., March 1850). All these forms appear to be closely 

 allied to Zooglcea termo, if not generically identical with it. 



According to Cohn there is not the slightest difference 

 heivfeen Polytomauvella, Ehr., and Chlamydomonas pulvisculus. 



The general summary of his inquiries may be thus stated — 

 That most of the Mycophycece, agree in family, and even in 



* Upon this subject vide Fresenius, ' Beitrage zur Mycologie.' Part I. 



