MOTIONS OF INSECTS. 467 
were still to be seen descending from above, and twinkling like stars in the 
sun, so as to draw the attention of the most incurious. The flakes of the 
web on this occasion hung so thick upon the hedges and trees, that baskets 
full might have been collected. No one doubts, he observes, but that 
these webs are the production of small spiders, which swarm in the fields 
in fine weather in autumn, and have a power of shooting out webs from 
their tails, so as to render themselves buoyant and lighter than the air.? 
In Germany these flights of gossamer appear so constantly in autumn, 
that they are there metaphorically called “ Der fliegender Sommer” (the 
flying or departing summer) ; and authors speak of the web as often hang- 
ing in flakes like wool on every hedge and bush throughout extensive 
districts, 
Here we may inquire —Why is the ground im these serene days covered 
so thickly by these webs, and what becomes of them? What occasions 
the spiders to mount into the air, and do the same species form both the 
terrestrial and aérial gossamer? And what causes the webs at last to fall 
tothe earth? I fear I cannot to all these queries return a fully satisfactory 
answer; but I will do the best Ican. At first one would conclude, from 
analogy, that the object of the gossamer which early in the morning is 
spread over stubbles and fallows—and sometimes so thickly as to make 
them appear as if covered with a carpet, or rather oyerflown by a sea of 
gauze, presenting, when studded with dew-drops, as I have often witnessed, 
a most enchanting spectacle—is to entrap the flies and other insects as 
they rise into the air from their nocturnal station of repose to take their 
diurnal flights. But Dr, Strack’s observations render this very doubtful ; 
for he kept many of the spiders that produce these webs in a large glass 
upon turf, where they spun as when at liberty, and he could never observe 
them attempt to catch or eat—even when entangled in their webs—the 
flies and gnats with which he supplied them ; though they greedily sucked 
water when sprinkled upon the turf, and remained lively for two months 
without other food.? As the single threads shot, by other spiders are 
usually their bridges, this, perhaps may be the object of the webs in ques- 
tion; and thus the animals may be conveyed from furrow to furrow or 
straw to straw less circuitously, and with less labour, than if they had 
travelled over the ground, As these creatures seem so thirsty, may we not 
conjecture that the drops of dew, with which they are always as it were 
strung, are a secondary object with them? So prodigious are their num- 
bers, that sometimes every stalk of straw in the stubbles, and every clod and 
stone in the fallows, swarms with them, Dr. Strack assures us that twenty 
or thirty often sit upon a single straw, and that he collected about 2000 in 
half an hour, and could have easily doubled the number had he wished it: 
he remarks, that the cause of their escaping the notice of other observers 
is their falling to the ground upon the least alarm, 
As to what becomes of this immense carpeting of web there are different 
opinions. Mr. White conjectures that these threads, when first shot, might 
be entangled in the rising dew, and so drawn up, spiders and all, by a brisk 
evaporation, into the region where the clouds are formed.’ But this seems 
almost as inadmissible as that of Hooke, before related. An ingenious and 
1 Nat. Hist. i, 825, 
2 Neue Schriften der Natunforschenden Gessellschaft 2u Halle, 1810, y. Heft. 
5 Nat. Hist. i. 826, 
HHS 
