S. J. MC'iNTIRE ON CHEAP AI0S TO MICROSCOPICAL STUDIES. 71 



any comments of mine on their merits are unnecessary, since 

 tliey are already known to many of our members.* I liave been 

 keeping some aquatic specimens in them during the past fort- 

 night and upwards ; and during that period repeated observations 

 have convinced me that those who ivill, have it in their power 

 cheaply, and without much trouble, to write many fresh chapters 

 of the " marvels of pond life." 



Breeding Cages for Microscopic Specimens. 



When I had the pleasure of calling the attention of this club 

 to the subject of Podur^e I alluded to certain wooden cells which 

 I had found of great use in my investigations. Since then I 

 have had abundant experience of their utility, but having men- 

 tioned to Dr. Gray the only difficulty I encountered at times — 

 that of the cells warping when wetted — he suggested the em- 

 ployment of sheet cork, siTch as is sold for lining entomological 

 cabinets. I tried it, and after about three months' experience I 

 have every reason to be much obliged to Dr. Gray for the sug- 

 gestion. For most of the purposes to which I have applied 

 them, they are now perfectly adapted, and exceedingly cheap, a 

 dozen of them costing about half a crown. I make them thus : — 

 A sheet of cork (varying in price from 4d. to Is. or more, according 

 to its thickness and quality), is cut into six or eight pieces, about 

 two inches by three and a half inches An oval hole is punched 

 out of the centre of each, and the edge of the aperture filed away in 

 a gradually sloping direction. 1 then take a piece of stout plate 

 glass of the same size, and put seven or eight layers of blotting 

 paper on it.f Then on this I place the cork cell just made, and on 

 the top a cover of the thinnest plate glass I can get, which I prefer 

 to be only a little larger than the aperture of the cell, and bind the 

 whole together with india-rubber bands. 



Having put the captives into the cell, I dip the end of it into 

 water, which immediately finds its way into the interior, aided by 

 the blotting paper. Food is introduced by slipping the cover a 

 little to one side, and if care is taken that the inmates are not sub- 

 jected to many changes of temperature, but kept cool, and that 

 sufficient, yet not too much food • and moisture are introduced, 

 observations on individual microscopic insects may be continued for 



* See page 46. 



1 1 prefer to use the very best cork, and pink blotting paper. 



G 



