Different types of nests of trap-door spiders.
<p><i>a</i> is represented the nest of a French species of <i>Atypus</i>, one of the Atypidae; this is included here merely for contrast; <br><i>b</i> represents the cork type of nest; Moggridge believed that in this type the tunnel is always simple, but Atkinson ('86) describes a branched nest with a door of the cork type.<br></p><p><br>
The following have the door of the wafer type as follows: <br><i>c</i>, a single-door, un-branched wafer nest; <br><i>d</i>, a single-door, branched wafer nest; <br><i>e</i>, a double-door, unbranched wafer nest, and e1, the lower door of the same; <br></p>
<i>f, g,</i> and <i>g1</i>, three double-door, branched wafer nests, <i>f </i>and <i>g</i> <br>differing in the form of the second door, shown at <i>f1</i>, and <i>g2</i>.
John Traherne Moggridge (? -1874)
<i>The Spider Book</i>. John Henry Comstock . 1912 by Doubleday, Page &amp; Company in Garden City, New York .  <a rel="nofollow" class="external text" href="https://archive.org/stream/thespiderbook00coms#page/234/mode/1up">p. 234</a>