48 KOYAL ASIATIC SOCIETY, (CEYLON BRANCH;) 



often with outspread wings and legs. Allow them to remain 

 in the spirits for a fortnight or so, according to their size* 

 until you think all watery matter has been extracted from 

 their bodies by the action of the spirit. Then transfer them 

 to spirits of turpentine, there to remain until they become 

 tolerably transparent. Minute insects will turn so in a few 

 days after immersion, but large ones take a much longer 

 time. As soon as this transparency shews itself the insect 

 is fit for mounting in Canada balsam. If it is of the size of 

 the common house fly, a cell should be used, which can be 

 a ring of glass* cut from a glass tube and cemented on to 

 the glass slip described at the commencement of this paper* 

 Put your fly into this cell, and drop upon it sufficient balsam 

 to fill the cell to overflowing ; then take a circle of thin glass 

 of the diameter of the cell, and shut in the fly. The super^ 

 fluous balsam will be pressed out at the sides of the cell, and 

 can be removed after it has been allowed to harden a little* 

 It is advisable to have an excess of balsam in the cell before 

 closing it, as it prevents the possibility of air vacancies, 

 which produce unsightly bubbles. Still with all precaution 

 taken, a few small bubbles may be present on the closing of 

 the cell, but these will disappear in course of time. Small 

 insects are more easily dealt with, for they may be laid upon 

 a plain slip of glass, a small globule of Canada balsam placed 

 over them, and then covered with a thin glass, square or 

 round, which must be let very gently down, as any undue 

 pressure might crush the object, I sometimes use a very 

 shallow cell of home manufacture, punched out of thin 

 sheet lead, which answers very well. After the balsam has 

 been put to the object, the slides should be kept in a flat 

 position for some months until the balsam becomes tough, 



* Such cells are procurable at all London opticians who sell materials 

 for mounting. 



