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[Vol. 91 
higher percentage of burrows than those that were not. Although 
the experimental design allows consideration of only the importance 
of the presence of prey, higher rates of burrow establishment in the 
presence of food may imply either a nutritional advantage or a 
response to prey availability. 
With respect to nutritional differences, even though burrowing 
behavior is innate and may be observed as early as in late pre- 
emergent spiderlings which have not fed (pers. observ.), the 
successful establishment of a burrow may be more likely if a 
spiderling is able to obtain food prior to dispersing. Many lycosid 
spiderlings disperse after only a short time on the mother (e.g., 
about seven days, Higashi and Rovner, 1975) and do not feed prior 
to dispersal (Foelix, 1982). My observations of field populations of 
other Geolycosa indicate that spiderlings may cling to the mother 
for up to three weeks and some young remain in the maternal 
burrow for at least one molt after leaving the mother’s abdomen as 
Engelhardt (1964) found in Trochosa spp. A possible advantage of 
this extended association with the mother is that those spiderlings 
that remain may receive nurishment by sharing prey captured by the 
mother, as in Sosippus floridanus (Brach, 1976), or by cannibalism. 
Hallander (1970) observed cannibalism in Pardosa pullata of the 
same brood, even in situations of high prey density. I held broods of 
G. turricola and G. patellonigra without food for six weeks and 
observed few instances of cannibalism. Cannibalism, therefore, is 
probably not a primary means of obtaining predispersal nourish- 
ment in Geolycosa. At present, I do not have information as to 
whether older juvenile Geolycosa that remain in the burrows are 
able to obtain food on their own. I have observed spiderlings 
clinging to the turret rim in a foraging position but I have never 
observed prey capture. 
The means of obtaining predispersal nourishment (if such is 
obtained) notwithstanding, a lack of food per se does not preclude 
burrow construction. Significantly more burrows were constructed 
in the groups which were provided with food but many unfed 
spiderlings (average 40.8%) successfully constructed burrows. Also, 
observations of lab held and starved G. patellonigra indicated that 
burrowing may occur well after two weeks post emergence (pers. 
observ.). 
