1974 ] 
Quintero — Web of Spilasma tubulofaciens 
309 
Fig. 6. S. tubulofaciens (Hingston), frontal view of web and retreat 
(entrance of retreat closed), drawn from photographs. Suspension lines 
shaded. 
Size indicator: 10 mm. 
broad, lower end of the retreat had a transverse, single opening with 
two lips, the posterior lip being the longer. The lining of the anterior 
lip appeared thinner and more flexible. The supporting lines were 
strong, reinforced with silk, and contained numerous moss fragments, 
particularly close to the insertion on the retreat. There were also 
remains of insects and vegetable matter. The spider remains inside 
the retreat, and waits head down for its prey, a characteristic position 
of the orb-weaving spiders. When I offered living ants, which I 
placed on the lower corner of the catching web, the female dashed 
out of the retreat rapidly, wrapped its prey (Fig. 9), bit it, and 
promptly returned to the retreat, without eating the prey. 
Discussion. By changing the position of the hub (coincident in 
this case with the retreat) to a peripheral, uppermost position, an 
additional load of tension has been placed on the suspension lines. 
Additional tension has also been brought to these lines by the taut, 
almost straight line, to which they have been drawn. Consequently 
the spider has carefully reinforced the lines with extra layers of silk, 
enclosing different building materials, and they no longer function 
in prey capture but to support the rest of the web and the retreat. 
It differs from S. artifex Simon, which Simon, in 1896, described as 
hanging the retreat and catching web from a single perpendicular 
