BACTERIA. 41 



branching. The filaments are not readily divisible into 

 elements and form dense tangled masses. 



The organism is very pleomorphons, and sometimes 

 forms streptococcns-like chains, the individuals of which 

 are often spoken of as spores, though not possessed of 

 spore-like qualities. Sometimes the filaments break up 

 into bacilli-like fragments. The ends of the filaments often 

 form enlarged club-shaped masses, which are looked upon 

 by some as reproductive in function, but by the majority 

 are thought to be degenerative in nature. They are well 

 illustiated in the common ray fungus of actinomycosis. 



All of the ray fungi belong to the streptothrix group. 



Classification. — Leeuwenhoek, when he first saw the 

 bacteria — and his successors even to so recent a date as 

 to include Ehrenberg and Dujardin — did not doubt that 

 they belonged to the infusoria. They are now known to 

 belong to the vegetable kingdom. 



The extremely simple organization of bacteria naturally 

 places them among the lowest members of the vegetable 

 kingdom, in that class of the Cryptogamia known as 

 Thallophytse, comprising the algae, lichens, and fungi. 



The algae are mostly water-plants, containing chloro- 

 phyl and obtaining their nourishment from inorganic 

 substances. 



The lichens are plants, some of which contain chloro- 

 phyl. They live upon inorganic matter, which they 

 generally absorb from the air. According to the new 

 view of the subject, some, if not all, of these plants are 

 regarded as fungi growing parasitically upon algae. 



The fungi, the lowest group of all, are minute or large 

 plants, mostly devoid of chlorophyl, living upon organic 

 matter, which they obtain as saprophytes from decom- 

 posing animal and Vegetable matters, or as parasites 

 upon the tissues or juices of living animals or plants. 



This lowest family, the fungi, are divisible into the — 



Hyphomycetes or Mucorini, or moulds; 

 Saccharomycetes, or yeasts; and 

 Schizomycetes, or bacteria. . 



