Note 66 — PART II.

Since writing the above I have learned, thanks to a better method which I have recently adopted for preserving the nests for examination, that sometimes the lower door, instead of being free within the tube and only attached to the lining by the hinge, is surrounded on either side by a delicate silk web, which extends from either edge of its lower surface to the silk walls of the tube below and forms a sort of double gusset. This admits of the movement of the lower door in the way described above, but perhaps serves, together with the solid appendage at the extremity of the free end of the door (that away from the hinge), to prevent the door from being driven too far in an upward direction and thus becoming so tightly jammed as to make the spider a prisoner in her own nest. I think it possible that the lower door is always attached to the tube in this way, but, as it parts readily from the silk on either side when the earth which supports the tube is removed, it very frequently appears to be free, as I have represented it in Plates IX., X., and XI.