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, hut 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. 
I nsects 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 hv 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 
