28 JOURNAL OF THE TRINIDAD 



has shown that active bacteria contain 83.42 per cent, of water, 

 while in the dried state they consist of 



A nitrogenous bod v called mycoprotein ... 84.20 



Fat... ^ ... ... ... ... 6.04 



Ash ... ... ... ... 4.72 



Undetermined substances ... ... 5.04 



In structure bacteria consist of a cell wall which can be 

 shown by the action of iodine to consist of cellulose, and cell 

 contents which yield mycoprotein. In some species this is homo- 

 geneous, in others granular. Sometimes the power of retaining 

 certain aniline stains is present, but not always. This is of great 

 importance in determining the nature of some bacilli, for example, 

 those of tuberculosis and leprosy. 



In some bacteria the cell protoplasm contains starch granules 

 as in Clostridium butyricum; in others, .such as Beggiatoa, 

 sulphur is present. In the latter organism the cells also contain 

 a special pigment bacterio-purpurin. In other cases the pigment 

 granules are outside the cells as in Bacterium prodigiosum, while 

 in Bacillus pyocyaneus the pigment is partly within and partly 

 outside the cells. 



Many species of bacteria are provided with a gelatinous 

 envelope, the result of either secretion from the cell or absorption 

 of moisture and swelling of the outer layer of the cell wall. 

 When this gelatinous material forms a matrix in which numbers 

 of bacteria are congregated it is called a zoogloea. This zooglcea 

 condition is a resting stage of the organism. 



The forms of bacteria as will be shown presently are very 

 various and have given rise to no little controversy. 



With regard to the reproduction of bacteria, though, as 

 implied by the name Schizomj'cetes, the characteristic mode of 

 increase is by fission, there are other processes which resemble 

 fructification. These are divided into two groups distinguished 

 by the formation of endospores and arthrospores. 



In endospore formation the protoplasm becomes granular, 

 and at certain points in the chain of rods specks ap}i>ear which 

 gradually develop into highly refractive circular or oval bodies. 

 After a time the cell walls and protoplasm disappear and the 

 spores are set free. This is well seen in Bacillus subtilis and 

 Bacillus antliracis. 



In arthrospore formation as seen in Leuconostoc mesenteroides 

 certain elements in the chain of cocci, apparently not differing 

 from the rest, enlarge, and the walls become tougher and more 

 refractive. The remaining cells die, and these enlarged cells are 

 set free as spores capable of reproducing the growth in suitable 

 soil. 



