94 Synopsis of the Bacteria and Yeast Fungi. 



In the teeth of a dog suffering from Pyorrhoea alveolaris, 

 and subsequently in the bite of other carnivorous and her- 

 bivorous mammals, sheep, cattle, pigs, horses, cats, etc. 

 The subdivision of the larger cocci and the septation of 

 the finer threads were only made visible by staining. 



This is considered by Miller as affording a very strong proof of the 

 truth of ZopPs theory. It resembles Beggiatoa alba and Crenothrix 

 Kiihniana. Miller also found the same stages in L. buccalis (see 

 Fig. 2"ja) in carious teeth ; in this the cocci penetrated into the tooth 

 more deeply than the rods, and they in turn than the longer threads 

 (supra, p. 72). It is to be remarked, however, that what are here 

 called cocci, rods, and spiral forms are not the exact counterparts of 

 typical Micrococci, Bacteria, and Spirilla. (See also F. Y. Clark, in 

 Johnston's Dental Miscellany, 1879, p. 447, who describes a Bacterium 

 in the teeth, 1*5-3 /* long, *5 /* broad, of a somewhat spiral form.) 



SPIRILLUM. 



115. S. rosaceum, Klein (Quart. Jour. Micr. Set'., xv., 



1875, p. 381). 



Resembling S. Undula, but reddish in colour ; colour- 

 ing matter insoluble in water, alcohol, or chloroform. 



Seems to be identical with S. rufum, Perty (Prit chard, 

 " Infusoria," p. 534), and possibly not different from the 

 form recorded by Geddes and Ewart (Proc. Roy. Soc., 1878, 

 p. 482). It is distinct from S. sanguineum, Cohn, with which 

 it has been confounded (see also Bacterium rubescens, p. 85). 



1 1 6. Spirulina alba, Van Tieghem (Bull. Soc. Bot. 



France, 1880, p. 177). 



Absolutely colourless. Filaments very long and slender, 

 resembling S. tenuissima. Coils so close together as almost 

 to touch and form a hollow tube. Turning actively round 

 its axis, and also oscillating laterally as a whole. 



Forming a thin white layer on the muddy bottom of 



