168 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



Orbitelariee is vertical, but the corresponding section of the web of the Bas- 

 iUca spider, Fig, 13, d d, might be properly described as horizontal, or 



rather as a blending of the horizontal with the vertical. In other 

 Linked words, if a horizontal orb attached at the circumference in the 

 , usual way were to be lifted up by a thread fastened in the centre, 



it would assume the shape of the dome in the web of the Basil- 

 ica spider. In point of fact, this effect might be produced from the charac- 

 teristic snares of those species w^hich have been described in the opening of 

 this chapter. If, for example, one were to fasten a thread to the central 

 point of the orb of Tetragnatha or the Orchard spider, and gradually lift 

 it until the orb should assume the dome shape, he would have a snare very 

 strongly resembling that of Basilica. The principal difference would be that 

 the apron of intersecting lines beneath the dome of the Orchard spider ap- 

 pears in Basilica's web as the underlying curtain ; and in addition thereto 

 a similar mass of spinningwork appears above the orb. Another difference 

 is that the spiral concentrics all have the notched appearance of the few 

 central concentrics which compose what I have named the- notched zone. 



Several years after I had observed and published the description of Bas- 

 ilica's web and its relations, substantially as described above, I w^as greatly 



delighted to have my study confirmed by the observations of Dr. 

 Observa- Q^orge Marx, of Washington, D. C. He had received my ac- 



r. J count with much skepticism, as indeed did other arachnologists. 

 firmed. ^ ^ 



Unfortunately, my description of this entirely new form of orb- 

 web, and the remarkable deduction therefroifi, w^ere based upon observations 

 of a single example both of spinningwork and spider making it. I had no 

 doubt of the accuracy of my notes and sketches, which were made with 

 care and painstaking, for at the first glance I a[)})rehended the importance 

 of the discovery. Nevertheless, I greatly desired to find other exam})les, 

 but searched in vain in the neighborhood of my camp.^ 



It w^as, therefore, with unusual satisfaction that I learned from Dr. 

 Marx that he had observed several specimens of Basilica in the shrubbery 

 on the beautiful })arked grounds surrounding the Agricultural Department 

 and other public buildings of the national capital. He confirmed my de- 

 scription of the character of the web, and added thereto an obser- 



,, _ vation of the manner in Avhich the dome is reared. The hvpo- 



the Dome. , . , . . • • , r ^ • i" • i 



thetical case, given in my original paper, of the manner in wliicli 



the domed orb of Basilica might be (substantially) erected out of the hori- 

 zontal orb of the Orchard spider, proved to be a fortunate anticii)ation of 

 the exact method of the spider. Dr. Marx says that the orb is at first a 



^ I had gone to Texas witli a sperial purpose, namely, tlu' study of tlie Ajxrirullmal 

 Ants; and it was al)soliitt'ly necessary, in order to follow my line of study and experiments, 

 that I sliould limit the time j^iven to other observations. 1 have often rej^retted tiiat I 

 could not have spent a day or two in searching the surrounding district for other examples 

 of Basilica. 



