204 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 
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to a taut trapline which is connected with the centre. There is no slack 
coil, and no springing of the net as with the Triangle spider. 
The industry of Theridiosoma is united to that of the full orb makers, 
on the one extreme, by its orbicular character and its beaded spirals; but 
with that of Hyptiotes, on the other extreme, by the independent character 
of the rays, the nature of the trapline, and the entire mode of operating 
the snare. The facts necessary to trace these affinities I have already 
given. 
Some of the striking differences I have also recorded, and they may 
thus be summarized. The web of Hyptiotes is a single sector; that of 
Theridiosoma has four or more sectors united. Hyptiotes com- 
Differ- mands one line with her feet, the trapline and its continuation ; 
ute. Theridiosoma commands several axes, which are connected with, 
iohes: but not continuous of, the trapline. Hyptiotes has her head, — 
Theridiosoma her abdomen towards her snare. Hyptiotes habit- 
ually hangs to the trapline, back downward; Theridiosoma generally sits 
upon a foot basket of lines, back upward. Hyptiotes shoots forward when 
her net is sprung; Theridiosoma shoots backward; but both spiders move 
toward their webs. Hyptiotes holds her slack coil between the two hind 
feet; Theridiosoma between the fore feet. In these differences, the points 
wherein Theridiosoma varies from Hyptiotes show a quite apparent ap- 
proach to the behavior of the full orb makers. Thus the distance which 
heretofore had separated between the far away extremes of the spinning- 
work of the Orbitelarize, has been bridged over by the industry of our 
little indigenous aranead—the Ray spider. It is to be remarked that 
while structurally the Triangle spider is as widely removed from Epeira 
as economically, the Ray spider is more closely allied structurally to the 
latter than the former. 
In correspondence with arachnologists, concerning the true position of 
the Ray spider, the question was raised as to the accuracy of the statement, 
in my paper of 1881, that the interradial lines of Theridiosoma 
are covered with viscid beads. The question is certainly one of 
great importance. Mr. Cambridge, in establishing the genus, 
which he regarded as a connecting link between Theridium and Epeira, 
alludes to the fact that Dr. Koch describes the snare as consisting simply 
of a few lines spun from plant to plant. “This habit,” he declares, “ to- 
gether with some structural considerations, exclude it from the Epeirides.” 
Thus, it would seem that the spinning habit of the creature bore quite as 
strongly as its structure in determining its systematic position. Had Mr. 
Cambridge then been familiar with the real spinningwork of the species 
he might have had no hesitation in relegating it to the Orbitelariz. 
The question was raised, whether the spiral lines of my Ray spider 
might not have been covered with flocculent strings, somewhat after the 
manner of the snares of Hyptiotes and Uloborus. As the spider is desti- 
Viscid 
Spirals. 
‘ coe iaon le 
Pe eee ee TOR ee 
‘ 
