ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 623 



in 1 p.c. hematoxylin. 4. Decolorising in 15 p.c. aqueous solution of 

 perchloride of iron for a few minutes. 5. Rapid washing in hydro- 

 chloric-acid-alcohol (0*75 HC1 to 100 C 2 H 6 0). G. Absolute alcohol, 

 and removal of celloidin if necessary. 7. Clearing in xylol or cedar- 

 wood oil, as the case may be. 



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



Aceton-Paraffin Imbedding Method.* — A. E. Sitsen has tested this 

 method, and finds that for diagnostic purposes it is of value, but for 

 demonstrating the finer details there should be a preliminary fixation. 

 Pieces 1-2 mm. thick are placed for 15-80 minutes in 10 p.c. formalin 

 and then for 80 minutes in aceton. After this they are placed in 

 paraffin for an equal length of time. 



Material fixed in chromic acid salts requires to be soaked in water 

 for 24 hours. The method is also available for alcohol-fixed tissues. 

 For demonstrating glycogen the material should not be fixed before it 

 is immersed in aceton ; fat requires to be blackened by osmic acid, as it 

 disappears if not previously fixed. 



Rapid Method of Preparing Large Numbers of Sections.! — 

 G. C. Huber, after alluding to the difficulties attending the preparation 

 of sections for large classes, describes the procedure adopted by him, 

 which is a combination of the warm water method of flattening paraffin 

 sections and the Obregia-Gulland method. 



The fixed and dehydrated tissues are impregnated with paraffin in 

 partial vacuum. Serial sections are then made and flattened out in 

 warm water contained in a tray specially devised for the purpose. 

 While still in the water, or in a sugar-dextrin solution, the ribands are 

 floated on to glass plates. On removal, the plates, covered with series of 

 sections, are drained and dried. The paraffin is then removed in the 

 usual way (heat and xylol), after which the plates are transferred to 

 absolute alcohol. The next step is to cover the sections with the 

 following solution : photoxylin 10, absolute alcohol 100, ether 500. 

 When the photoxylin is set the film of sections is removed by immersing 

 it in water. It may then be cut up into any desired lengths, and 

 stained and mounted in the usual way. 



If, however, the sections are required for future use, they may be 

 removed by placing the plate in water, and then rolling the film round 

 a glass rod, and afterwards storing the rolls in 80 p.c. alcohol. 



For the minute details of the procedure, which are very clearly 

 given, the original should be consulted. 



! (4) Staining- and Injecting-. 



Staining Piroplasma Muris.J — H. B. Fantham stained films of the 

 blood and smears from the internal organs of the white rat by various 

 modifications of the Romanowsky method, especially a combination of 

 the methods of Laveran and Plimmer, using Bleu Borrel, erythrosin, and 



* Centralbl. Allgem. Pathol, u. Pathol. Anat., xvi. (1905) pp. 774-5. 

 t Zeitschr. wiss. Mikrosk., xxiii. (1906) pp. 187-96 (2 figs.), 

 j Quart. Journ. Micr. Sci., 1. (1906) pp. 493-516 (1 pi.). 



