ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



253 



is centrif uged for half an hour. Films are made from the deposit, and 

 stained in the usual way. 



Glaeser, K. — TJntersuchungen uber die Herkumft des knorpels an regeneri. 

 erenden Amphibienextremitaten. 



Arch. f. Mikr. Anat. u. Entwikl., lxxv. (1910) pp. 1-39 (1 pi. and 16 figs.). 



(3) Cutting-, including' Imbedding and Microtomes. 



Cutting 1 Thin Parallel Slices of Brain Substance.* — K. Berliner 

 describes an apparatus (fig. 39) which has been in use at the hospital 

 in Giessen for a number of years. The material to be cut is fixed on a 

 sliding base (Sch) which moves along grooves in the bars L, L, one of 

 which is provided with a scale. The vertical rods, F, F, guide the 



Fig. 39. 



movements of the knife or fretsaw, and so vertical slides of equal thick- 

 ness can be made. For fresh material a kuife is used, but in the case 

 of brains hardened in Miiller's fluid or in bichromate it is found that a 

 fine fretsaw is more suitable. 



* 



Apparatus for Whetting a Microtome Knife. — J. Lendvai has 

 found Apathy's method of whetting the best. This consists in the appli- 

 cation of emery, Vienna chalk, iron-oxide, or diamantin powder, on 

 three mirror-glass plates. For this purpose the author has devised a 

 special apparatus, which has been constructed for him by the firm of 

 C. Reichert. The three plates are necessary because the materials are of 



* Zeitschr. wiss. Mikrosk.,xxvi. (1909) pp. 382-4. 

 t Tom. cifc., pp. 203-5 (5 figs.). 



