MEMOIR OF SWAMMERDAM. 57 



especially, which he could separate from all the other 

 parts, and exhibit in a manner that excited the sur- 

 prise and admiration of all who had an opportunity 

 of observing them. For the purpose of cleansing 

 thoroughly the internal parts, he was accustomed to 

 inject water into them by means of a small syringe, 

 after which they were filled with air and dried ; in 

 this way they could be preserved for examination at 

 any future time. Not only was he thus successful 

 in investigating the internal organs of recently killed 

 insects, but he could examine them in specimens which 

 had been preserved for years in balsam and spirits 

 of various kinds. This afforded him the advantage 

 of dissecting foreign species, many of which being of 

 much greater size than such as occur in Europe, 

 * present all the parts in a more conspicuous manner. 

 He could preserve the nerves in such a perfect state, 

 that they retained their flexibility for a long time, and 

 looked as if newly extracted from the living subject. 

 Insects of a soft and fleshy consistency, he preserved 

 in a variety of ways. Sometimes he punctured them 

 in various places with a needle, and expressed all the 

 fluids and moisture in their bodies through the pores 

 thus made ; he then filled them with air by means 

 of slender glass tubes, dried them in the shade, and 

 lastly anointed them with oil of spike, in which a 

 little resin had been dissolved, by which means 

 they retained their proper forms for a long while. 

 With caterpillars he devised the plan which has 

 often been followed since, namely, making an inci- 

 sion near the tail, and gently squeezing out all the 



