ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 763 



The wax mass consisted of 3 parts white wax, 2 parts powdered 

 colophonium, 1 part Venetian turpentine. The mass was stained with 

 Berlin blue or with cinnabar. The mass was injected while the body 

 of the bird was still warm, and when the operation was completed the 

 body was cooled down in cold water, and then, after the lapse of a few 

 hours, was transferred to pure hydrochloric acid for maceration. When the 

 maceration was complete, the preparation was cleansed in running water. 



The photoxylin and celloidin injections are made by dissolving the 

 commercial article in equal parts of absolute alcohol and sulphuric ether, 

 and mixing the mass with zinc- white or cinnabar. 



The solution injected is at first of a thin, syrupy consistence, after- 

 wards followed by a thicker. As the solvents evaporate quickly, it is 

 necessary to give a few turns of the piston-screw from time to time so 

 as to keep the tension up. According to the size of the animal, it 

 takes hours or days for the injection mass to set properly. After having 

 been macerated in pure hydrochloric acid, the preparation is washed in 

 running water, and afterwards preserved in a mixture of alcohol, glycerin, 

 and water. 



As hydrochloric acid did not always act satisfactorily, the following 

 coiTosive menstruum was substituted : oxalic acid 6, pepsin 1 ■ 5, distilled 

 water 200. This medium w r as used, after preliminary treatment, with 

 hydrochloric acid, and the digestion was effected in a thermostat at 40° C. 



Celluloid injection masses were chiefly used for blood-vessels. Cellu- 

 loid shavings were dissolved in pure acetone, and the solution mixed with 

 cinnabar or zinc-white. 



For microscopical sections, the thoracic viscera (trachea, lungs, and 

 heart) were placed within a bell jar, from which the air could be 

 exhausted below and gelatin solution made to flow in above. 



For fixing the material for microscopical purposes, five methods were 

 tried : absolute alcohol ; formalin, alone and with the addition of 5 p.c. 

 acetic acid, and of saturated solution of sublimate ; Zenker's and Miiller's 

 fluids. The sections were stained by Van Gieson's and by Weigert's 

 methods, and with kresofuchsin. 



Creosote as a Dehydrating Medium for Imbedding in Paraffin.* 

 W. Pavlow recommends the following procedure, which he finds has 

 advantages over the usual method of dehydrating with alcohol. The 

 objects, fixed in any kind of fluid, are transferred without previous 

 dehydration to creosotum fagi for 4-24 hours, according to size, and 

 then immersed in pure creosote for 2-8 hours more. On removal, the 

 superfluous creosote is mopped off with blotting paper, and then the 

 objects are placed in xylol or toluol for one hour, after which they are 

 imbedded in paraffin in the usual way. 



Injection of Fine Vessels.t — P. Konascko successfully and easily 

 injects the organs of small animals by the following procedure. When 

 it is desired to inject, say, the portal system of the kidney of the frog, 

 a canula is introduced into the vena cava inferior or the vena abdomi- 

 nalis anterior. These large vessels are then injected with warm colourless 



* Zeitschr. wiss. Mikrosk., xxii. (l'J<>5) pp. 186-7. 

 t Tom. cit.. pp. 179-80. 



