ceeding rapidity, and in this respect is in strong contrast with the mem- 

 bers of the genus Pachylomerus, though the young ones of that genus 

 work more rapidly than the older ones When beginning the nest in a 

 patch of moss the spider will dive down into the moss and begin turn- 

 ing rapidly in all directions, at the same time spinning threads to fasten 

 together the pieces of moss around and over it, I have watched four 

 different ones make the nest, two beginning in moss which I had placed 

 over the eaith, and two beginning in soil. Two of these I had make a 

 nest several times, and thus far everyone has first entirely closed the en- 

 trance to the tube by building a sort of dome above it. Later, in one 

 case a week, cutting through this and making the folding door. 1 Usual- 

 lv while at work near the surface of the earth it will burrow out in differ- 

 ent directions and elevate the surface of the earth. This I think is part- 

 ly for the purpose of providing a place to put the earth which it excavates 

 from the lower portion of the tube, as I have seen these filled up; and 

 in one specimen, after the tube was about 2 cm. deep I observed the 

 same habit of digging and cementing to the edge of the tube, as observed 

 in the case of Pachylomerns caribivorus and 4-spinosus. This individual 

 made the dome by carrying up three sides regularly until it had com- 

 pletely covered the entrance. Usually in making the dome earth is 

 placed on and about the edge of the tube, occasionally applying viscid 

 liquid and spinning threads over it. Then the spider would, with its an- 

 terior legs and palpi pull the edge over the tube. This operation would 

 ba repeated until the dome was complete. 2 When moss is convenient the 

 door is made almost entirely of moss and silk; each door is a surface of 

 a half circle, is hung by a semicircular hinge, and the two meet, when 



1 Note. — In the Encyclopedia Brittannica, 9th edition, 1875, Vol.11, p. 291. 

 O. P. Cambridge says: "The present writer was once told by a gentle n an \vlv> had 

 formerly resided in the West Indies that trap-door spiders invariably made the tube 

 and lid of one continuous, solid, homogeneous piece, and then cut out the lid v ith ihe 

 fakers. This account, especially as coming from anon Naturalist seems impiobable, a 

 spiders fakers being in no way fitted apparently for such an operation." Where the 

 silk linining was thin, it would be a very easy matter for a spicier to cut through, and 

 then repair the roughness by cementing on particles. Ii is probably an exaggeration to 

 say that they "invariably"construct them in that manner, but I should not be surprised 

 if some species made the trap, door in the manner described by this non "naturalist." 



2 I have never seen this spider press the lid on the ends of its mandibles as does 

 P. caribivorus. I think this shows the adaptation of the special armature of the man- 

 dbile of P. caribvorus, and related forms, for fastening the earth to the lid. P. car- 

 ibivorus usually makes no thread in applying the viscid liquid to the door while ad- 

 ding particles, but puts it on as a cement. The large point of the mandibles, which is 

 covered with short strong spines serves admirably to punch the earth irregularly into 

 the portion of the door already made, and causing it to adhere firmly. 



