210 PROCEEDINGS OF THE ACADEMY OF [1888, 



spins the silken lining of her well known and much admired trap 

 ■door nest. 



4. The Nesting Tube Spun in Sections. — It was further determin- 

 •ed with reasonable certainty that the spider builds its tube in sec- 

 tions. A letter from Miss Anna Wittfeld, after I returned from 

 Florida, informed me that the spiders had spun complete tubes with- 

 in the jars which I had left under her care. The question was at 

 once raised, were these tubes completed by adding to the section 

 which had already been observed? From correspondence with Miss 

 Wittfeld the information was obtained that the tubes had been 

 finished as I had conjectured, by adding to the portions previously 

 formed. We may, therefore conclude first, (1) that the mode of 

 constructing these tubes is for the first time fully determined ; sec- 

 ond, (2) that the original section, of greater or less length as the 

 ■case may be, is spun in the manner now determined and described ; 

 and third, (3) that additional sections, of probably about the same 

 length, are added thereto according to the fancy or necessity of the 

 builder, and constructed in the same manner as the preceeding one. 

 It is thus within the power of Atypus to lengthen out her tube and 

 ■extend along the trunk to any desirable height, the web surface 

 available as a snare for taking food. Thus, also, as she ascends along 

 her arboreal hunting ground she carries with her the protecting 

 "walls of her tubular home, which is truly her castle. 



A large number of tubes was collected, and these I cut open with 

 the view of determining whether any trace of this mode of spinning 

 by sections had been left in the form of seams or joints ; but nothing 

 of the sort was found. The points of juncture were so skilfully 

 •covered over that they differed in no respect from the texture of 

 other portions of the tube. The silk on the inside, however, was of 

 beautiful smooth white color, decidedly in contrast with the appear- 

 ance of the outside. In many specimens examined the upper ex- 

 tremity of the tube was made of perfectly white silk which apparent- 

 ly had been quite recently spun, showing an addition to the tube 

 -either for the purpose of repairing and strengthening, or else of ex- 

 tending the old nest. This observation upon the nests spun in nat- 

 ural site quite harmonizes with the conclusion reached from the ac- 

 tion of Atypus in confinement.^ 



' For an account of the English Atypus piceus making a new nest as observed 

 by Rev. O. Pickard-Cambridge, See Annals and Mag. of Natural History, Vol. 

 viii., p. 241, 187G. 



