WOLF- AND TRAP- DOOR SPIDERS. 
213 
The Vagrant or Wolf Spider . — This insect catches its 
prey by stealthily stalking it until within distance near 
enough to admit of a sudden dart being successful in 
effecting capture. Some species, before making the final 
dart {e.g, Saltieus scenicus ), fix a line of web upon the 
surface over which they are creeping, so that whether their 
station is vertical or horizontal with reference to the prey, 
they can leap fearlessly, the thread in any case preventing 
their fall. Dr. H. F. Hutchinson says that he has seen 
this spider crawling over a looking-glass stalking its own 
reflection . 1 
The following is quoted from Buchner 
Less idyllic than the water-spider is onr native hunting- 
spider ( Dolomedes fimbriata ), which belongs to those species 
which spin no web, but hunt their victims like animals of prey. 
As the Argyroneta is the discoverer of the diving-bell, so may 
this be regarded as the discoverer or first builder of a floating 
raft. It is not content with hunting insects on land, but 
follows them on the water, on the surface of which it runs 
about with ease. It, however, needs a place to rest on, and 
makes it by rolling together dry leaves and such like bodies, 
binding them into a firm whole with its silken threads. On 
this raft-like vessel it floats at the mercy of wind and waves ; 
and if an unlucky water-insect comes for an instant to the sur- 
face of the water to breathe, the spider darts at it with light- 
ning speed, and carries it back to its raft to devour at its ease. 
Thus everywhere in nature are battle, craft, and ingenuity, all 
following the merciless law of egoism, in order to maintain 
their own lives and to destroy those of others ! 
Trap-door Spiders . — These display the curious in- 
stinct of providing their nests with trap-doors. The nest 
consists of a tube excavated in the eaxth to the depth of 
half a foot or more. In all save one species the tube is 
unbranched ; it is always lined with silk, which is con- 
tinuous with the lining of the trap-door or doors, of which 
it forms the hinge. In the species which constructs a 
branching tube, the branch is always single, more or less 
straight, takes origin at a point situated a few inches from 
the orifice of the main tube, is directed upwards at an acute 
2 Loc. tit., p. 323. 
1 Nature , vol. xx., p. 581. 
