OF THE ORDER ARANEIDEA. 251 
thus occasioning the nodding motion with intervals of 
repose apparent in its prey. 
September 18th. Temperature 61°. At 10" 20™a.M. 
a female Zegenaria civilis seized a House-fly with its 
fangs near the middle of the mesonotum, and did not 
relax its hold for more than an hour. The struggles 
of the fly became gradually more feeble, till they 
ceased altogether at 10° 47" a.m. The nodding 
motion of the victim, and all the attendant circum- 
stances, were as conspicuous in this instance as in 
the preceding one. 
September 18th. Temperature 64°. <A female Se- 
gestria senoculata penetrated with its fangs the right 
side of the mesonotum of a House-fly at 1" p.m., but 
did not deprive it of life till 1"29™e.m. The spider 
kept its hold about an hour; and a nodding motion 
of the fly, regularly accompanied by the act of deglu- 
tition in its destroyer, with brief and simultaneous 
pauses in both, was observed during the entire 
period. 
1847. July 15th. Temperature 71°. At 5°3™ p.m. 
a brilliant Green Fly (A/usca cesar) was pierced by 
the fangs of a female Avelena labyrinthica near the 
posterior extremity of the abdomen, on the under- 
side. After retaining its hold about ten minutes the 
spider transferred it to the middle of the mesoster- 
num, perforating the part and rapidly extracting the 
fluids of its prey, whose existence terminated at 
55 26" p.m. A nutation of the fly was constantly 
