On Flagellated Protozoa, &c. By Edgar M. Grookshanh. 915 



than to any other," but he was of opinion at the time that they 

 did not appear exactly the same. 



Five years later Surra broke out in British Burma. A Keport * 

 was issued by Veterinary Surgeon Steel who was deputed to in- 

 vestigate the outbreak. Steel confirmed the communicability of the 

 disease to dogs, horses, and mules, by ingestion and inoculation, but 

 he considerably supplemented Evans' views as to the nature of the 

 disease by careful thermometric observations. These finally led 

 him to regard the disease as a true relapsing fever, closely resem- 

 bling relapsing fever in man ; at the same time it is worth recording 

 that until Steel observed the presence of the parasite described by 

 Evans he regarded the outbreak as malarious in origin, and pro- 

 visionally termed it gastric typhoid. In the Burma outbreak, as in 

 the Punjab epidemic, considerable evidence was adduced in favour 

 of regarding the disease as being due to bad water supply. 



Steel succeeded in staining the organism with anilin dyes, but 

 his description of the parasite in the fresh state, differs very 

 materially from that given by Evans. 



Steel failed to recognize the round body tapering in front to a 

 neck. To him the bodies appeared thick in the middle, gradually 

 diminishing in size in either direction, with a blunt and rigid 

 extremity at one end. The opposite end he described as tapering 

 in such a way as to produce a subspiral prolongation which was 

 uncurled and lashed about freely like a whip. This tail was 

 described as slender in relation to the general size of the parasite, 

 but under the highest power available, the presence of a colourless 

 flagellum could not be detected, nor, he adds, did the movements 

 of the blood-constituents indicate its existence. 



Steel also failed to see the slightest sign of the two fin-like 

 papillae on each side as described by Evans, an opinion in which he 

 was supported by Lewis. 



These two observers, Evans and Steel, also differed as to whether 

 the movement be called spiral. Steel felt convinced that their 

 movement was as much of that nature at times as can be expected 

 from organisms with so open a corkscrew shape, while Evans 

 maintained an opposite view. In the dried and stained specimens 

 Steel observed that they retained their subspiral form of body 

 and markedly spiral form of tail. 



Steel found that the disease could be communicated to the dog 

 and to the monkey, and then discussed the resemblance of the 

 parasite to the spirillum of relapsing fever in man. 



From the different appearances presented by the parasite when 

 in the living state and when dried and stained, Steel thought that 

 there was probably a still closer resemblance to the living spirillum 



* Veterinary Surgeon J. A. Steel, A.V.D., 'An Investigation into an 

 obscure and fatal Disease among transport mules in British Burma, 1885.' 



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