430 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



liard day's work. Specimens as large as the central hemisphere of 

 a rabbit can be stained and imbedded whole. 



I append my notes on the spinal cord of a frog, showing the 

 times used in the various processes :— 



Cord put into 3 per cent, nitric acid, 2 hoiu'S. 



Seventy per cent, alcohol, 6 hours. 



Stained in haematoxylin, 4 hours. 



Seventy per cent, alcohol, overnight. 



Ninety-five per cent, alcohol, 24 hours. 



Oil of cloves, 24 hours (did not wish to imbed till next day) ; 

 then, 



Turpentine, stir half-an-hour. 



Turpentine and paraffin, 1 hour. 



Paraffiji, 1 hour. 



It should be remembered that these cords imbed easily. 



One caution further ; select paraffin, if possible, which is bluish- 

 transparent, and which rings slightly when struck. The white 

 opaque sort is by no means as good. Any addition of paraffin-oil, 

 tui'pentine, &c., to soften the paraffin, renders it granular and brittle, 

 and is decidedly injurious to its cutting qualities." 



Williams' Freezings Microtome adapted for Use with Ether.* — 

 The original form of this Microtome was described and figui-ed at 

 pp. 697-9 of vol. i. (1881). It subsequently occurred to Mr. J. W. 



Fig. S3. 



Groves that it would be an improvement if it were adapted for the use 

 of ether as a freezing agent instead of ice and salt. Mr. J. Swift 



* Journ. Quek. Micr. Club, vi. (1881) pp. 293-5 (2 figs.). 



