420 SUMMARY OF CURRENT RESEARCHES RELATING TO 



should be perfectly even. The final sealing gelatin ring may be made of 

 more concentrated gelatin, rendered as thick by evaporation of a portion 

 of the original preparation as will flow easily from the brush. The flow 

 will depend to a great extent upon the temperature of the room. This 

 gelatin seal can also be used for holding the solution of phosphorus in 

 carbon disulphide when this solution is employed as a mounting medium. 



(6) Miscellaneous. 



Blocks.— For the loan of the blocks to figs. 34, 35, 36, 37, 38, 39, 

 40, 41 and 44, we are indebted to the Quekett Microscopical Club. 



