T. S. SMITHSON ON A NEW ARRANGEMENT OF GROWING SLIDE. 83 



that, when desired, three separate slides can be kept under 

 treatment at the same time. 



Mr. Pagan has been good enough to allow me to bring his 

 invention before the Club, and I have much pleasure in doing 

 so, as I think it supplies a want that has been long felt by 

 microscopists, and it is capable of doing a large amount of 

 valuable work in elucidating problems in the life history of the 

 many organisms which still remain very imperfectly known, 

 owing to the difficulty of watching their development during 

 lengthened periods. 



