English: Plate XI, fig. A. — The upper part of a nest of Nemesia meridionalis concealed in a plant of Ceterach fern ; A 1 and A 2, a minute cork-door, closed and open, which I saw constructed by a very young spider [either Cteniza fodiens, or, more probably, Nemesia caementaria] at the mouth of a hole in the mass of earth containing the nest of N. meridionalis figured at A. This hole may be seen on the right of the fern. B, the door of a small nest of N. meridionalis, as seen from above, in its natural position in a steeply sloping bank ; B I, part of the same nest placed in an upright position, and showing the surface door open and the lower door closing the branch; B 2, the same with the lower door pushed across so as to close the main tube ; B 3, 4, and 5, different views of this second door. [All the figures in this plate are of the natural size. ]