INTRODUCTION OF THE MICROSCOPE 73 
took, he likewise overdid this, and yielded himself to a sort 
of fanatical worship until the end of his life, in 1680. Had 
he possessed a more vigorous constitution he would have 
been greaterasa man. He lived, in all, but forty-three years; 
the last six or seven years were unproductive because of his 
mental distractions, and before that, much of his time had 
been lost through sickness. 
The Biblia Nature.—It is time toask, What, with all his 
talents and prodigious application, did he leave to science? 
This is best answered by an examination of the Biblia Na- 
tur@, under which title all his work was collected. His treatise 
on Bees and Mayflies and a few other articles were pub- 
lished during his lifetime, but a large part of his observations 
remained entirely unknown until they were published in this 
book fifty-seven years after his death. In the folio edition 
it embraces 410 pages of text and fifty-three plates, replete 
with figures of original observations. It “contains about a 
dozen life-histories of insects worked out in more or less 
detail. Of these, the mayfly is the most famous; that on 
the honey-bee the most elaborate.’ The greater amount of 
his work was in structural entomology. It is known that he 
had a collection of about three thousand different species of 
insects, which for that period was a very large one. There 
is, however, a considerable amount of work on other animals; 
the fine anatomy of the snail, the structure of the clam, the 
squid; observations on the structure and development of the 
frog; observations on the contraction of the muscles, etc., etc. 
It is to be remembered that Swammerdam was extremely 
exact in all that he did. His descriptions are models of 
accuracy and completeness. 
Fig. 16 shows reduced sketches of his illustrations of the 
structure of the snail. The upper sketch shows the central 
nervous system and the nerve trunks connected therewith, 
and the lower figure shows the shell and the principal muscles. 
