FIELD NATURALISTS' CLUB. 37 



life history of the bacillus lepra?, for it is by no means certain 

 that it has yet been cultivated, though many have claimed 

 success. Inoculations of animals have failed, though the bacillus 

 is very resistant. In a fowl which I inoculated with a piece of 

 leprous nodule, I found leprosy bacilli more than two years after 

 inoculation, though there had been no development of the disease. 



Time will not allow me to do more than mention a few of 

 the many other interesting members of this genus. The Bacillus 

 id nl lei has been fully worked out, and is now generally accepted 

 as the cause of glanders. The Bacillus alvei has been shown to 

 produce foul-brood in bee-hives. The - bacillus of malignant 

 oedema, of septicaemia of mice, of swine typhoid, of swine erysipelas 

 are also accepted as pathogenic in animals. 



It has been shown that the inoculation of garden earth in 

 mice and rabbits induces fatal tetanus. At the point of inocu- 

 lation abscesses form and from these abscesses bacilli mixed with 

 other organisms have been obtained and cultivated. A culture of 

 this mixture produces the same disease. Recent researches by 

 Kitasato and others have added much to our knowledge of the 

 bacillus of tetanus. 



Among the saprophytic bacilli I can only refer to the Bacillus 

 subtilis or hay bacillus, a very common and widely distributed 

 organism, and a frequent intruder in other cultivations. 



5. Vibrio. This is a a genus containing screw shaped threads 

 in long or short links. Spore formation is present. 



One species is described, Vibrio rugula. It occurs in veget- 

 able infusions causing fermentation of cellulose. The rods are 

 curved or w r ith one shallow spiral. They form swarms and grow 

 out into threads curved in a screw like manner. Endospores are 

 formed at one extremity, which then becomes enlarged giving the 

 rod the appearance of a pin. 



6. Clostridium. This genus resembles bacillus except that 

 spore formation takes place in characteristically enlarged rods 

 One species is pathogenic, causing a disease in cattle which is 

 variously known as blackleg, quarter-evil, rausch-brand or symp- 

 tomatic anthrax. 



A common species is Clostridium butyricum which converts lac- 

 tic acid in milk into butyric acid and produces the ripening of cheese. 



Group III. — Leptotrichece. 



This group possesses cocci, rods and thread-forms wdiich shew 

 a distinction between base and apex. The threads are straight 

 or spiral. 



The group is divided into four genera. 



1. Crenothrix. In this genus the threads are articulated ; 

 the cells are without sulphur ; the habitat is water. 



