66 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 
This sitting position is not unusual, but is not common; I have noticed 
several species which appear at times to indulge in it. The attitudes of 
the body, while substantially like those figured, vary somewhat accord- 
ing to circumstances. Epeira vertebrata, E. arabesca, and E. benjamina 
are some of the Orbweavers observed in this posture. No doubt the 
position gives a grateful relief from the ordinary attitude, by changing 
the direction of tension, if nothing more. 
IV. 
Under examples given in Vol. I., illustrating the physical and mechan- 
ical powers of spiders, was a case of a small fish captured by a species of 
Dolomede or Lycosid spider. The case has excited much in- 
AFish terest, and it is gratifying to have it supported by a like well 
ace authenticated instance. Mr. Francis R. Welsh, of Philadelphia, 
writes me that a spider once killed two sun fish, each about two 
inches long, that he had in a basin in his room. After having attacked 
the first fish it ran over the water and fastened upon the second, which 
was also at the time apparently well and vigorous. Mr. Welsh drove the 
spider off, but the fishes died in a few hours. The basin was kept in a 
second story room of a country house at Chestnut Hill, and climbing vines 
covered the outer walls, nearly approaching a window close by the basin. 
It was inferred that the aranead entered the window from the vines. Mr. 
Welsh could not identify the spider, and could describe it only in a general 
way; but judging from the figures in my books he supposed it might 
have been either a Dolomedes or Agalena nevia. It would be entirely 
possible for the former animal to accomplish the deed, for in the cocoon- 
ing season Dolomedes lurks in the bushes near her egg nest (Vol. IL, 
page 145), spun among the leaves. One would hesitate, however, to think 
of Agalena as a creature of amphibious habits. 
The same gentleman, referring to the engineering habits of spiders, as 
described Vol. I., page 211, and especially of the use of counterpoise, tells 
me that he saw a spider one day cut a dead leaf out of its web, 
Counter- which was dropped and hung by several threads. It then cut it 
ee - down again twice, the leaf each time dropping and hanging lower. 
‘Mr. Welsh could not see if the spider attached any special threads 
to the leaf, but she ultimately used it as a counterpoise to her snare. 
V. 
Many Orbweavers have a curious habit of moving themselves rapidly 
upon their webs when excited by any cause which attracts their attention 
or awakens fear. It is particularly noticeable in the genera Argiope and 
Acrosoma. This action occurs when the spider is stationed at the centre 
when eh ee | a 
