1 6 BACTERIA 



thrix. To the former belongs the diphtheria and tubercle bacillus, 

 both of which are said to have branching involution forms, while to 

 the latter belong the organisms of actinomycosis and Madura foot. 

 The Chlamydobacteriacecz and Beggiatoa are Saprophytes. These 

 require special technique for their laboratory culture. 

 "/^The Yeasts _oi ' Blastomycetes or budding fungi are next in order. 

 They consist of sharply and ckmbly outlined, refractive, oval bodies 

 which may grow out into short stalkl^Called mycelia. ^They grow 

 well in the laboratory and may produce pig- 

 ments. They are much larger than the bac- 

 teria (10-25 V- l n g)- They multiply by bud- 

 ding with a separation and removed growth 

 of the young form. They may produce a local 

 or general infection in man, Blastomycosis. 

 They are used in beer making. The com- 

 p IG- I5 . B a c i 1 1 i monest genus is Saccharomyces. 



showing capsules The Moulds QiJIyphomycetes represent the 



(Greene's Medical < ^^""1 



Diagnosis.) next highest group of the plant algae. They 



are characterized by a greater prominence of 

 the mycelium over simple segments or bodies. They are wide- 

 spread in nature and many are pathogenic. They multiply by 

 segmentation of the mycelia into gonidia or by the development of 

 special spore masses called sporangia. Further refinements of the 

 spores into sexual elements is known. They are chiefly of interest 

 to the physician on account of the skin diseases that they occasion. 



THE CHEMICAL COMPOSITION OF BACTERIA. 



x Bodies^ oj bacteria contain_water > _salts__ertain albumins, and 

 bodies that mayhe^extracted with etherX Among the latter are 

 lecithin, cholesterin, and triolein.^In the tubercle bacillus, fatty 

 acids and wax have been found. In others, xanthin bases, cellulose, 

 starch, chitin, iron salts, and sulphur grains have been discovered. 

 The essential albumin of the cell-body is highly nitrogenous and is 

 called mycoprotein. The salts in the ash are mostly composed of 



