HISTORICAL. 15 



tranquilla, lamellula, pulvisculus, uva, which it 

 is impossible to identify with the species at pres- 

 ent recognized. The genus Vibrio " vermis incon- 

 spicuus, simplicissimus, teres, elongatus" enclosing 

 under thirty-five specific names, with the true 

 bacteria, some organisms belonging to other 

 classes of the animal and vegetable kingdoms. 



In the classification of - the infusoria given by 

 Bory de Saint-Vincent in the " Encyclopedic 

 Methodique " (1824) and afterwards in the "Dic- 

 tionaire Classique d'Histoire Naturelle " (1830) the 

 bacteria are distributed in two different families 

 of the microscopic gymnodae, the monadaires and 

 the vibrionides. Besides the monads, properly so 

 called, of which the Monas termo has been pre- 

 served by the greater part of the bacterologists, 

 the monadaires include some veritable infusoria, 

 which have no relation with the monads. It was 

 the same with the vibrionides, of which the genera 

 Vibrio and Mellanella included some beings very 

 different in their organization. Indeed, beside 

 some veritable vibrios, bacteria, and spirilla, 

 constituting the genus Mellanella, Bory placed 

 some nematoid worms, such as the Anguillula 

 of vinegar. 



With Ehrenberg (1838) and Dujardin (1841) 

 the family of the vibrioniens was established upon 

 characters more homogeneous, and their species 

 upon distinctions truly scientific. But these two 

 observers, followed in this by M. Davaine, deny 

 completely the affinities of the elongated bacteria 



