740 THE ANIMAL PARASITES OF MAN 



found that S. broiichialis is an organism presenting marked poly- 

 morphism, a feature that has only been determined by the examination 

 of numerous preparations from the deeper bronchial regions of various 

 patients. 



S. broiichialis varies in length from 5 //, to 27 /i, and its breadth is 

 about o'2//, to 0*6 //,. These variations are due to the processes of 

 growth and division. Many of the parasites measure either 14 /A to 

 i6//,long, or 7 ^ to 9 JJL, the latter resulting from transverse division 

 of the former. The ends show much variation in form, but approach 

 the acuminate type on the whole. The discrepancies in dimensions 

 given by the very few previous workers on the subject are probably 

 the result of the measurement of a limited number of parasites. All 

 such sizes can be found on some occasion during the progress of the 

 disease, when a larger number of spirochaetes is examined. 



The movements of S. broiichialis are active, but of relatively short 

 duration, when it is removed from the body. The number of coils 

 of the spirochaete is rather an index of its rapidity of motion than a 

 fixed characteristic of the species. 



The motile phase of S. broiichialis is succeeded by one of granule 

 formation, the granules or coccoid bodies serving as a resting stage 

 from which new spirochaetes are produced. The formation of 

 coccoid bodies and reproduction of spirochaetes from them can be 

 observed in life. 



S. broiichialis is a species distinct from the spirochaetes occurring 

 in the mouth. It differs from them in morphology, pathogenicity 

 and in staining reactions. It is not a developmental form of any 

 bacterium, and is an entity in itself. 



The passage from man to man is effected most probably by means 

 of spirochaetes, and especially coccoid bodies, that leave the body in 

 the spray with expired air and by way of the nasal secretions. Owing 

 to the fragility and short life of S. broiichialis extracorporeally, the 

 resistant coccoid bodies in air, in dried sputum and dust, and possibly 

 also on the bodies of flies and other insects, are probably instrumental 

 in inducing attacks of bronchial spirochaetosis in human beings, espe- 

 cially those having a lowered bodily resistance, such as occurs after 

 a chill. Ltirie (December, 1915), has described a case from Serbia. 



The Spirochaetes of the Human Mouth (see p. 122). Two 

 species of spirochaetes were recorded as occurring in the human 

 mouth about forty or fifty years ago. These are Spirochccta buccalis, 

 Steinberg (often ascribed to Cohn, 1875), and S. dentinm, Miller 

 (often attributed to Koch, 1877). 



The most recent work on S. dentium and S. buccalis is that of 

 Fantham 1 (July, 1915), who observed the parasites ascribed to Cohn 



1 Annals 'Irop. Med. and Parasitol., ix, p. 402. 



