166 A MANUAL OF BACTERIOLOGY 



Bacillus putrificus coli. It was first isolated from 

 faeces, and measures about 3 //, in length. On gela- 

 tine it has an opalescent appearance, but finally 

 becomes a yellow colour. It is motile microbe, 

 which occurs in long or short threads. Spore- 

 formation has been observed. 



Bacillus epidermidis. It was discovered in the 

 fragments of epidermis taken from between the toes- 

 This microbe measures from 2 '8 to 3 yu, in length, 

 and 0*3 //, in breadth; it forms spores from 1*2 to 

 1'5 p in length, and 0'3 to 0'4 p in breadth. It 

 grows only sparsely on nutrient gelatine and agar- 

 agar. On potatoes it forms a characteristic super- 

 ficial skin. 



Bacillus of Nitrous Fermentation. Dr. P. F. 

 Frankland 1 has recently isolated from soil a bacillus 

 which converts ammonia into nitrites. This mic- 

 robe will be described under the heading of ' the 

 microbes of the soil/ 



Bacillus megaterium. This microbe was dis- 

 covered by the late Dr. De Bary on boiled cabbage. 

 The rods are motile, and measure 10 p, x 2 -5 p. 

 They occur singly and in chains, and grow on gela- 

 tine and agar-agar, forming a whitish layer. On 

 potatoes at 20 C. yellowish-white dots are formed. 

 B. megaterium is an aerobic microbe, and produces 

 spores. 



Leptothrix luccalis. This microbe occurs in the 

 slime of the teeth, on the epithelium of the mouth, 

 etc. j in other words, it is one of the microbes of the 

 mouth. It occurs as isolated bacilli or threads, 



1 Philosophical Transactions of the Royal Society, 1890, p. 107. 



