24 
Psyche 
[March-June 
Table 5 
Descriptive statistics for some structural features of radius to frame con- 
nections (R-F’s). For each feature 5 webs built by 4 different spiders were 
observed. R-F’s were rather variable with respect to these features, as 
indicated by the coefficients of variation. Note that frame threads at 
R-F’s were thicker than threads at SS-R’s and NS-R’s (see Table 2 and 
Table 4). 
Feature 
Mean 
Coefficient 
of 
Variation 
Range 
No. of 
Measure- 
ments 
Length of Sleeve 
158.7 li 
38 
100/i-250 At 
8 
Number of Strands 
in Radius 
34.1 
24 
19-45 
8 
Thickness of Frame 
8.4 H 
27 
5 fi- 12 H 
13 
It is interesting that a spiral to radius connection of another species, 
Cyrtophora citricola (Kullman, 1957) greatly resembled NS-R’s of 
A. diadematus. It had a similar configuration of threads, a non-zero 
junction, the spiral thread joining the radius as several strands, and 
a loose strand on the spiral thread. 
The Hub: 
When the spider completes the sticky spiral, she removes the 
threads at the hub and adds new ones. Here she sits when the web 
is completed and from time to time fastens more threads. 
At the only hub we investigated, there were thread connections 
resembling NS-R’s (Fig. 5a). Others were compound, with threads 
radiating from the junction in more than 4 directions, probably the 
result of two or more connections being made at the same place at 
different times. The shapes of some junctions from the hub (Fig. 
5b) were quite unlike the shapes of those from any other observed 
type of connection. There were many loose threads and strands of 
thread (Fig. 5a), perhaps the effect of changing tensions as the 
spider moved about the hub. The discovery of globules on threads 
