458 Mr. BLACKWALL’ s Observations to ascertain 
From the cylindrical figure of the phial, it follows that all the 
lines attached to its sides by their extremities, such as were ver- 
tical alone excepted, 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; 
thén ascending again to the greatest altitude it could attain, and 
dropping down by a thread to the bottom of the phial, over 
which it walked to the opposite side; it there drew the thread 
tight and made it fast, having prevented it from coming in con- 
tact with the glass previously by raising the abdomen a little. 
To this oblique line it united others, extending them in different 
directions, till by these means it established a communication 
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 were of two distinct species ; but as the technical diffe- 
rence of insects has engaged only a small share of my attention, 
I shall leave the task of identifying them to those who áre more 
familiar than myself with this branch of entomology. The sub- 
joined remarks on some of the characteristics of these insects, 
which are more conveniently illustrated by the pen than the 
. pencil, may serve to facilitate this object. 
One species has four of its eight eyes much larger than the 
other four. Two pair situated in the front or fore-part of the 
head are arranged thus *.-* , the relative size of the dots being 
nearly the same as that of the eyes. The other pair of small 
ones is placed in the upper part of the head, ànd on each side of 
it one of the remaining pair of large eyes is seated. This spider 
has the abdomen rather depressed; the anterior limbs, which it 
raises in a menacing manner when any thing approaches it, are 
longer 
