ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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kidney. They are best stained with fuclisin and methylen-blue. The 
third form is extremely small, and they are met with in considerable 
numbers in the blood. They are barely as thick as the tubercle bacillus, 
and their length is about double their breadth. They have the appear- 
ance of a small oblong, and they impart to the red corpuscles on the 
surface of which they are scattered a milled appearance. The author 
regards the first two kinds as being of the same nature, and analogous 
to the bacilli of fowl cholera and of rabbit septicaemia. 
The last two forms were found in the blood of all the viscera. 
Whether the first form is derived from the third form seems doubtful. 
Streptococcus Sanguinis Canis.* — Dr. K. L. Pitfield found in the 
blood of dogs a coccus which is actively motile, usually single, but 
occasionally in pairs. On agar or on bouillon it forms long chains, and 
examined in hanging drops, these chains can be seen to move about 
slowly. The coccus is easily stained, and is not decolorised by Gram’s 
method. Flagella could not be stained, but were seen occasionally. 
The organism grows well on the normal media, and does not liquefy 
gelatin. The growth is white. The streptococcus was found in 
healthy and diseased animals ; and while harmless to dogs, only causing 
a local abscess which healed rapidly, it was found to be pathogenic to 
rabbits and guinea-pigs. 
Ripening of Emmenthal Cheese.f — M. Ed. de Freudenreich finds 
that the microbic agents which effect the ripening of Emmenthal cheese 
are chiefly the lactic ferments. These organisms exist in ripenin g cheese 
in enormous numbers, while other bacterial species such as Tyrothrix 
are comparatively rare. The legitimate conclusion from this is that 
cheese-ripening is due to lactic acid bacteria, and that there is reason to 
hope that the art of cheese-making may be facilitated by the use of 
artificial cultures in the same way that bacteria are used for ripening 
cream. 
In the ripening of soft cheeses, however, Oidium lactis and yeasts 
appear to act in concert with the lactic ferments, for they certainly play 
some part in the ripening of these cheeses. 
Black Discoloration of Cheese and Cheese-Poisoning.J — The note 
of C. Besana on a sample of Parmesan cheese covered with black spots 
and smelling of garlic allows Herr G. Marpmann to indicate the causes 
of these conditions. The black spots are due to the presence of ferro- 
philous bacteria which form sulphides. The bacteria are motionless 
rodlets 2-3 /x long and 0* 8-1*0 /x broad. The ends are rounded, and 
the cells are distinguished by black polar chromatophores and grey 
granules ; many cells are black throughout. The pigment is produced 
only when the media contain iron, and the presence of iron and sulphides 
is easily demonstrable by the ordinary chemical tests. 
The garlicky odour is common to decomposing organic matter which 
contains phosphates, and is due to the presence of phosphuretted 
hydrogen. The presence of this compound can be demonstrated, and 
distinguished from sulphuretted hydrogen by the reaction to test-papers 
* Micr. Bulletin, xiv. (1897) p. 44. 
t Ann. de Micrographie, ix. (1897) pp. 385-409. 
% Centralbl. Bakt. u. Par., 2 te Abt., iv. (1898) pp. 21-6. 
1898 
R 
