300 OBSERVATIONS ON THE 
bules, not unlike small crystal beads or seed pearls 
thin strung on a clew of silk ; which, whether they 
were so spun by the spider, or by the adventitious 
moisture of a fog (which I have observed to cover all 
these filaments with such crystalline beads), I will not 
now dispute.” 
Messrs. Kirby and Spence, in their ‘ Introduction to 
Entomology,’ vol. i. letter xiii., state, that “the net 
of the Garden Spider is composed of two distinct 
kinds of silk; that of the radii not adhesive, that of 
the circles extremely viscid:” and this difference, 
they remark, “ when it is considered that both sorts 
proceed from the same instrument, is truly wonder- 
ful.” The fact, however, is even more extraordinary 
than it is represented to be by those distinguished 
naturalists ; for not only the Garden Spider, but every 
Geometric species with which I am acquainted em- 
ploys three distinct kinds of silk, if a liquid gum can 
with propriety be termed silk, in the construction of 
its net. The boundary lines, radii, and first formed 
spiral line being unadhesive, and possessing only a 
moderate share of elasticity, are evidently composed 
of a different material from the last formed spiral line, 
which is exceedingly viscid and elastic in a remark- 
able degree. Now the viscidity of the elastic spiral 
line may be shown to depend entirely upon the glo- 
bules with which it is studded ; for if they be removed 
by careful applications of the finger, a fine glossy line 
remains, which is highly elastic, but perfectly unadhe- 
