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Psyche 
[Vol. 91 
Sand was used as the burrowing medium in all cases. Spiderlings 
which were to receive food were given newly-hatched crickets at the 
beginning of the experimental period. A metal probe was used to 
make small crevices in the sand where necessary. Restricted 
randomization was used to assign roughly equal numbers of 
spiderlings to treatment groups (fed, unfed, etc.). Specimens were 
held in their test containers at normal room temperature and light 
for a period of 36 h, at which time I observed whether each had 
established a burrow or not. Previous observations indicated that 
burrows are usually established within the first 24 h after dispersal. 
Results 
The first set of hypotheses tested the independence of burrowing 
with the variables vegetation and crevice respectively within the 
levels of the variable prey (Table 2). The hypothesis that burrowing 
is independent of vegetation within a prey group (fed or unfed) 
was rejected for G. turricola but not for G. micanopy (Table 2). 
Both fed and unfed G. turricola showed a higher number of 
burrowers in the group that was provided with vegetation (86% and 
43% burrowing in the fed and unfed groups respectively). For G. 
micanopy, the number of burrowers is approximately the same for 
the fed spiders with and without vegetation. A higher percentage of 
the unfed G. micanopy burrowed when no vegetation was present 
(23% and 40% for the group with and without vegetation respec- 
tively). More spiders burrowed in the presence of a crevice than 
when no crevice was available for both fed and unfed G. micanopy. 
The second set of hypotheses tested the independence of 
burrowing and prey given the level of each of the other two 
variables. In every case, the hypothesis of independence was rejected 
(Table 2). In nearly every case, the percentage of spiderlings 
constructing burrows was lower in the unfed group. This is true for 
each level of the two variables, vegetation and crevice except for 
the unfed G. micanopy who were provided a crevice. In that case, 
more spiderlings constructed burrows than did not. 
Discussion 
The results indicate that, of those variables considered, prey was 
most strongly associated with the establishment of a burrow. In 
nearly every case, groups of spiderlings which were given food had a 
