ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 513 



Nutritive Value of certain Peptones for different Species of 

 Bacteria.* — H. Dunschmann compared three peptones : (1) Peptone 

 Defresne, obtained from the action of the pancreas on beef ; (2) 

 peptone Martin, obtained by digesting the minced stomachs of pigs by 

 means of the peptone they contain ; (3) vegetable peptone, obtained 

 from albuminoid substances extracted from leguminous vegetables, and 

 peptonised by means of papaiotine. The solutions used consisted of 

 3 p.c. peptone, 3 p.c. lactose, and 1 p.c. lemco. These were inoculated 

 with B. typhosus, B. coli, anthrax, and B. diphtheria,. For typhoid, 

 diphtheria, and anthrax, vegetable peptone gave by far the best results, 

 while with B. coli there was but little difference. When the medium 

 without lactose was tested by means of the same microbes, it was found 

 that B. coli throve much better on the Martin and Defresne's peptones 

 than on the vegetable, and that the vegetable peptone presents obvious 

 advantages for differentiating B. typhosus and B. coli. 



Kitt, Th. — Bakterienkunde und pathologische Mikroskopie fur Tierarzte und 

 Studierende der Tiermedizin. 



Wien : M. Perles, 1908, fifth and much enlarged edition, 

 v. and 578 pp., with more than 200 illustrations and 

 4 col pis. 



(2) Preparing- Objects. 



Demonstrating- Nervous Tissue of Hirudinea3.| — E. Mencl fixed 

 Hirudinefe in the following solution : — (1) Saturated solution of subli- 

 mate and distilled water, of each 500 grin. ; (2) chromic acid, 0*5-1 

 grm. ; (3) a trace of glacial acetic acid. The preparations were stained 

 with Heidenhain's hematoxylin, picro-magnesia-carmin, Delafield and 

 Bordeaux red, or orange G-, Apathy's gold chloride method, and with 

 Ramon y Cajal's silver method. 



Examining Catenata.J — V. Dogiel made intra vitam examinations 

 by teasing out the intestine which contained the parasites in sea-water. 

 The material was then transferred to a slide. Fixed preparations were 

 obtained by means of Flenmiiug's fluid, acetic sublimate and Carnoy's 

 mixture (absolute alcohol 75, acetic acid 25). Sections made from 

 material fixed in sublimate and acetic acid were stained with iron- 

 hsematoxylin. Those fixed in Flemming's fluid were treated mostly 

 with safranin, but some with picro-carmin, while for those fixed in 

 Carnoy's fluid hamialuin gave the best results. 



Studying the Development of Teeth in Castor Fiber. § — P. Heinick 

 decalcified the material in a mixture of 5 parts 96 p.c. alcohol, 1 part 

 strong nitric acid. The fluid was re-made and renewed every 3-4 days. 

 The material was not properly decalcified for from 8-11 weeks. After 

 this time the preparations were freed from the acid by immersion in 

 96 p.c. alcohol, to which precipitated chalk had been added. This took 

 from 6-8 weeks, the spirit being renewed every 3 or 4 days, until blue 

 litmus paper showed no acid reaction. The next step was to obtain the 



* Comptes Rendus, cxlvi. (1908) pp. 999-1001. 

 t Zeitschr. wiss. Zool., lxxxix. (1908) pp. 371-416 (2 pis.). 

 j Zeitschr. wiss. Zool., lxxxix. (1908) pp. 417-71 (3 pis.). 

 § Zool. Jarhb., xxvi. (1908) pp. 355-402 (2 pis.). 



Aug. 19th, 1908 2 M 



