1974] 
Rovner Knost — Wrapping of Prey 
399 
temperatures averaged 25.8 zb 2. 7° (SD) over the entire investi- 
gation. 
Initial observations were made on spiders in boxes identical to 
their bousing cages. Each individual had been food-deprived for up 
to 7 days. In this phase of our study we used the following types 
of prey: terrestrial isopods ( Armadillidium sp.), 6-8 mm; Japanese 
beetles ( Popillia japonica) } 10-12 mm; mealworm larvae, 18-20 mm; 
small grasshoppers (Cyrtacanthacridinae) , 6-8 mm; small ground 
crickets (Nemobiinae) , 10-13 mm; and vestigial-winged fruit flies 
( Drosophila ?nelanogaster) , 2 mm. We offered three prey at time 
— O, and additional single prey at + 10 and +20 min (all of the 
same species) in most of these tests. (For fruit flies, groups of eight 
were added at each of the three times.) Observation periods were 
at least 30 min in duration. The spider then was returned to its 
home cage with its captured prey. 
To determine the functions of the various spinnerets in wrapping, 
we sealed pairs of spinnerets with paraffin while female L. rabida 
were under C0 2 anesthesia. Two females underwent sealing of the 
anterior spinnerets; two had the anterior and median spinnerets 
sealed; and two, the median and posterior spinnerets. These spiders 
were subsequently observed and filmed (Bolex Macrozoom Super 
8 mm camera, Model 160) during prey-wrapping. We also exam- 
ined the silk on the prey and substratum, after chasing away the 
female from her just-wrapped prey. 
To study the preference of L. rabida (and, to some extent, L. 
punctulata) for the ground vs. the herbaceous stratum, we con- 
structed artificial “field habitats” in three terraria (0.2 X 0.4 X 0.2 
m high). Cardboard “foliage” was fixed in a plaster base which 
provided the “ground surface” on 24 of the terrarium bottom. The 
remainder of the glass bottom was left uncovered to provide an 
alternative ground surface in case the plaster had a repellent effect 
on the spiders (which turned out not to be the case). Vertical and 
sloping surfaces projecting into space were provided by the artificial 
foliage (Fig. 1). Spiders could climb to a height (limited by a glass 
lid) of 0.19 m. 
Three female L. rabida (tagged with non-toxic enamel) were 
housed in each terrarium. (Three individuals were cannibalized in 
the course of this experiment and were replaced with equivalently 
tagged substitutes.) To prevent possible conditioning effects, we fed 
the spiders on the ground as often as on the foliage. (Feeding was 
done at times other than the daily observation periods.) We observed 
the nine spiders for 2-hr blocks of time each day for 10 days during 
