HORIZONTAL SNARES AND DOMED ORBS. 161 
of navigation by means of filament sails. ‘The first experiment was re- 
peated a number of times with various details upon several spiders, and al- 
ways with the same result. The gossamer thread was undoubt- 
“eater edly used as a sail, and the action of the wind bore the little 
ments,  2#Vigator to the shore. I frequently blew the tiny craft out to 
sea, either with my breath or by fanning with my hat. My stick 
could at any time arrest the thread by placing it a foot or more above the 
spider, and haying entangled it, I could draw her thereby in any direction. 
The filament was plainly seen floating above the spider, waving to and 
fro, generally bending above her back. 
The legs during motion were raised upward and bowed, thus holding 
the body well up from the surface, exactly in the attitude of a spider about 
to take aeronautic flight. They were kept quite rigid and motionless. The 
feet were spread out, describing the outline of an irregular octagon. I fancied 
that they were united by threads and that thus the spider sat upon a delicate 
raft of silk. Before spreading her sails the first act of the spider was to 
drop the abdomen to the 
surface, at which moment, 
I inferred, an attachment to 
the legs was made. I can 
hardly bring myself to be- 
lieve that the threads were 
attached to the water, al- 
though it may so have been, 
While the spider was un- Fic. 153, Epeira using her cocoon as a float. 
der sail the feet made a very noticeable ripple of wavelets as they were 
hurried along. She could accomplish short distances from the shore by 
running, without spreading sail, but when put well out she always re- 
sorted to the latter mode. However, any floating object which she met 
during the voyage was pretty sure to be taken advantage of as con- 
venient harborage. A downy seed which fell upon the water and drifted 
within reach of one of my aranead sailors was immediately seized by the 
creature’s fore feet, the spinnerets were set in motion, and the seed was 
overspun with a delicate floss, which converted it into a sort of float. 
In this connection I record an incident which may throw some light upon 
the development among Orbweavers of this interesting water habit. A large 
: female Epeira sclopetaria was collected, along with an abandoned 
Epeira cocoon, behind which it had spent the winter, at Atlantic City. 
and Her ,,., : : : ; 
Float. The spider was accidentally dropped into the Inlet, together with 
the flossy ball of the cocoon. She immediately threw out threads 
around the ball (Fig. 153), to which ‘she remained attached as to a buoy, 
and thus the two drifted along safely under the floor of a boat house 
and so out of sight. One associates such an action with the water walking 
and navigating of Tetragnatha, and wonders whether Epeira could ever, 
& 
