ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 83 



prepared from such a growth was found capable, when combined with 

 serum from a tuberculous patient, of binding complement. 



Cultivation of Spirochaeta recurrens.* — S. Hata gives an account 

 of his work undertaken in order to confirm that of Noguchi upon the 

 cultivation of S. recurrens. Xoguchi used fresh ascitic fluid in which a 

 small piece of rabbit-kidney was immersed. This is inoculated with a 

 small quantity of blood containing S. recurrens, and the organism multi- 

 plies when incubated at 37° C. for two to three days. The maximum 

 growth is reached on the eighth day. Spirochetes thus cultivated show 

 a tendency to rapid degeneration. Hata found it quite unnecessary to 

 cover the ascitic fluid with paraffin oil as Noguchi had recommended. 

 He found also that serum could be substituted for ascitic fluid. Blood 

 was drawn from the veins of a horse into a tall cylinder, and set aside 

 for the serum to separate. Serum is then put into tubes and mixed with 

 normal saline : <me part of serum to two of saline. The depth of fluid 

 in each tube is about 7 cm. The tubes are placed in a water-bath at 

 58° C, heated slowly to 70° C, and kept at that temperature for thirty 

 minutes. This semi-coagulated mass is a satisfactory substitute for 

 Noguchi's ascitic fluid. Small pieces of rabbit's kidney are pushed into 

 the mixture to rest at the bottom of the tubes. Hata found that the 

 buffyclot from normal horse's blood maybe used instead of kidney with 

 equally good results. This part of the clot is cut into small pieces and 

 pushed down to the bottom of the tube. This medium may be used in 

 place of Noguchi's ; the materials are more readily obtained, and uniform 

 results are obtained. 



New Medium for Cultivating Gonococcus. j- — Aug. Lumiere and 

 J. Chevrotier declare that the medium they have devised is eminently 

 suitable for the cultivation of gonococcus. It is prepared as follows : 

 A solution of G grrn. of albumen in 1000 c.cm. of beer wort is auto- 

 claved at 115° C. The medium is filtered while hot, and, after having 

 been alkalinized, it is sterilized again at 110° C. for ten minutes. 



It is advantageous to add 15 c.cm. horse or ass serum to 15 c.cm. 

 of the wort medium, but this addition is in no wise indispensable. 

 During sterilization it is important that the tubes should be kept 

 sloped. This recommendation presumably refers to the second steriliza- 

 tion. Gonococcus, whether old or recent, flourishes in this medium, 

 and its cultivation is as easy as that of the majority of micro-organisms. 

 The authors mention that different races of gonococcus, recognizable 

 hy their size, retain their primitive characteristics even unto the tenth 

 generation. 



(3) Cutting-, including- Embedding- and Microtomes. 



Leitz' New Sledge Microtome. J— This apparatus, which is described 

 by S. Becher, resembles the Minot type of microtome to the extent 

 that the knife is stationary and the object movable. As will be seen 



* Centralbl. Bakt., lte Abt. Orig., lxxii. (1913) pp. 107-12. 



t Comptes Eenduh, clvii. (1913) pp. 1097-9. 



j Zeitschr. wiss. Mikrosk., xxx. (1913) pp. 192-202 (2 figs.). 



G 2 



