44 
Psyche 
[March 
in the natural habitat, and discusses those behavioral and eco- 
logical factors which may contribute to making this animal an 
edge species. 
Methods 
Individuals of the brush-legged wolf spider, Schizocosa crassipes 
(Walckenaer), were observed as they interacted in the natural habi- 
tat at Stroud’s Run State Park, Athens Co., Ohio, USA. Adults 
of both sexes are approximately the same size (body length = 7-10 
mm, carapace width = 3-4 mm, leg span = 27-30 mm), although 
striking sexual dimorphism exists. For example, the female’s varie- 
gated, patterned brown coloration contrasts with the male’s black 
coloration and gray/ white band down the midline of the cephalo- 
thorax and abdomen. Molting to the adult occurs in late May, 
at which time the males develop conspicuous tufts of black hairs 
on the tibiae of the forelegs with smaller brushes on the patellae. 
These small, ground-dwelling spiders are distributed throughout 
the eastern United States within the Deciduous Forest Forma- 
tion, and have been recorded as far West as Nevada (Fitch, 1963). 
In the present study, S. crassipes were found in abundance on leaf 
litter at the forest-meadow interface in an area approximately 
2 * 15 m, half of which was shaded and half exposed to sunlight. 
Observations were conducted continually from 1100-1600 hours 
every other day for 14 days during May 19-31, 1973, and air tem- 
perature was recorded during each observation period. I moved 
systematically around the study area every 10 min, waiting 5 min 
after each move before resuming observations. Thirty-five hours 
in the field resulted in 17.5 hr of recorded observations and totalled 
1050 one-minute observation periods. Protocol was recorded on 
a battery-powered tape-recorder, and included the number and 
sex of all conspecifics crossing within 1 cm directly in front of a 
male observation spider every minute. An earlier criterion of any 
spider approaching another within 3-5 cm, regardless of direction, 
was discarded because so many spiders were involved that accurate 
counts could not be taken. 
An observation spot was approximately 60 cm in diameter arbi- 
trarily divided into 12 sectors with the perimeter corresponding 
to the face of a clock. Following each move around the field, data 
recording began with my position taken as 6 o’clock, and observa- 
