274, . ON AERONAUTIC SPIDERS. 
formed with those sides chords to arcs of various 
magnitudes. Lowering itself from one of these 
chords to another, and applying the spinners to each 
in succession, the spider soon connected the whole 
of them together by a line; then ascending again 
to the greatest altitude it could attain, and dropping 
down by a line to the bottom of the phial, over 
which it walked to the opposite side, it there drew 
the filament tight and made it fast, having prevented 
it from coming in contact with the glass previously 
by raising the abdomen alittle. To this oblique line 
it united others, extending them in different direc- 
tions, till, by these means, it established a communi- 
cation with every part of the phial. As there was 
some difficulty in tracing these operations with the 
unassisted eye, lenses of the magnifying-powers of 
six and eight were employed. 
The spiders seen ascending into the atmosphere on 
the 1st of October, 1826, were of two distinct species 
—the Thomisus cristatus of M. Walckenaer and the 
Lycosa saccata of M. Latreille. The species noticed 
by me as remarkable for the skill it displayed in 
spinning its way up the sides of the phial in which 
it was confined, and for having existed seventy-five 
days without food or moisture, was 7homisus cristatus 
—Lycosa saccata being neither so expert in climbing, 
nor so tenacious of life under similar circumstances. 
The largest individuals of the first species observed to 
undertake aérial journeys measured % inch between 
