ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 247 



is made from the negative, by contact, on a second fast plate. From 

 this positive a second negative is made, and subsequently from this a 

 second positive, both by contact, on slow " process " or "lantern " plates. 

 Lantern slides showed the great improvement and practical absence 

 from the " fotr " thus obtained. 



B. Technique.* 

 (1) Collecting- Objects, including- Culture Processes. 



Multiplication in vitro of Treponema Pallidum.! — C. Lebailly 

 finds that liver and spleen infected with Treponema pallidum are 

 excellent cultivation media for these organisms. Pieces of liver and 

 spleen were cut out, with the usual precautions, from the body of a foetus 

 and incubated for 45 days. Examination at the end of 15 days showed 

 a great increase in the number of Treponemata : at the end of 45 days 

 there was no apparent increase in the number, and many were much 

 degenerated. 



Cultivation of Anaerobic Bacteria.! — J. Kursteiner finds that two 

 chief methods have been employed for the cultivation of anaerobic 

 organisms : (1) in which oxygen is apparently not excluded, as with 

 media containing reduced substances, or portions of organic tissue, or 

 as in mixed cultures with aerobes ; (2) in which oxygen is excluded, 

 either by covering the lower or upper layers of the medium with glass, 

 mica, or paraffin, by boiling the medium, by vacuating, by substituting 

 another gas for the oxygen, by absorption of the oxygen, or by a 

 combination of these principles. 



The author describes the most practical methods of R. Bum and of 

 J. H. Wright. 1. Burri employs a glass tube the size of an ordinary 

 test-tube, closed at either end by wool plugs and sterilised for two 

 hours at 160° to 180° C. ; a number of rubber corks kept under 

 sterilised water ; a sterile Petri dish, a scalpel, and a sheet of clean white 

 filter -paper ; 2 p.c. glucose-agar is prepared and sterilised, and when 

 cooled to 42° C. is inoculated and poured into one of the glass tubes, 

 which is then plugged with wool and a rubber cork, stood in cold water 

 to solidify the medium, and incubated at 30° C. or 37° C, and finally 

 on the top of the solid medium a few c.cm. of fresh sterilised agar are 

 poured and quickly solidified. After the colonies have appeared the 

 rubber cork is removed, and the cylinder of agar is allowed to slide out 

 of the tube on to the filter-paper, where it is dried ; sections of the 

 medium 1-2 mm. in thickness are then made with the sterilised knife, 

 and transferred directly to a Petri dish, placed on a dark ground ; by 

 carefully made cuts a colony is then removed from one of the sections 



* This subdivision contains (1) Collecting Objects, including Culture Pro- 

 cesses; (2) Preparing Objects ; (3) Cutting, including Imbedding and Microtomes ; 

 (4) Staining and Injecting ;(5) Mounting, including slides, preservative fluids, etc. ; 

 (6) Miscellaneous. 



t Comptes Rendus, cxlvi. (1908) pp. 312-14. 



X Centialbl. Bakt., 2te Abt. xix. (1907) pp. 1-26,97-115, 202-20, 385-88 (6 figs.). 



