78 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 
and as a consequence could only spin very imperfectly. It was observed 
to follow the habits of the hunting spider, which does not build a web, 
but catches its prey by stalking. This change of habit was only tem- 
porary, as the spider recovered its legs after moulting.1 Mr. Darwin also 
alludes to this incident. 
My observations are wholly contradictory of this. I have placed upon 
my vines an Epeira domiciliorum that had lost all the legs on one side, and 
_ found it to weave a serviceable web, although necessarily some- 
Spinning what imperfect. It hung upon its snare and trapped flies with 
after Mu- tair suce tee ften noted similar defects i riou - 
tilation, ‘27 success. lave oO similar defects in various spe 
cies always with the same result. Mr. Romanes’ inference as 
to the plasticity of instinct needs a little more confirmation. Indeed, 
the inference was long ago fully exploded by the observations of Dr. 
Heineken, a surgeon in the Island of Madeira during the early part of 
this century. This gentleman, in order to test the ability of orbweaving 
spiders to spin after mutilation, removed at intervals, successively, the legs 
of various individuals, with the following results: Epeira (Argiope) fasciata, 
with all the legs removed except the second and last on the left side and 
the last but one on the right side, thoroughly mended its web when two- 
thirds of it had been torn away. It maintained the same position and 
attitude as before mutilation, and in every respect had the manner of an 
Orbweaver. 
Another Epeiroid spider had all the legs removed except the first on 
the right side and the second and last on the left side, leaving the spider 
with but three legs. On the following day, filaments appeared in several 
directions. These were constantly added to, and in the course of two weeks 
a geometric web was formed equally perfect, but more sparing in quantity 
than one made by a spider in the same species and under the same mode 
of confinement, but healthy and unmutilated. The entanglement and taking 
of flies, and the conduct of the two spiders was in every respect similar. 
They were confined in large glass jars. A number of individuals were 
experimented upon with the same result. In the case of one tubemaking 
spider, the number of limbs was reduced to two, and the web entirely de- 
stroyed. Even then enough web was spun to cover the spider imperfectly 
and occasionally to entangle an exhausted fly. It lived for five weeks after 
mutilation.” 
1 Transactions Linnean Society, Vol. XT., page 393. 
2Dr. Heineken, On the Reproduction of Members in Spiders and Insects. Zoological 
Journal, Vol. LV., page 428. 1828-29. 
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