In the burrows made by the Mygalomorphae, on the contrary, the hinge is strong and highly elastic, its component silken threads being laid on in such a way that the door shuts with a snap when the occupant has passed in or out.
Other webspinning spiders (Tegenaria) have somewhat similar habits; and the male of the park-web spider (Atypus), one of the Mygalomorphae, taps the walls of the tubular web of the female before daring to bite a hole in it and descend into her burrow.
Prosoma as in the Mygalomorphae, except that the mesosternal area is long and narrow.
Trap-door nests are made by spiders belonging to two widely different groups, namely the Lycosidae or wolf-spiders, to which the true tarantula belongs, and the Mygalomorphae, containing the species which construct the best-known types of this style of burrow.