290 
Psyche 
[September-December 
Conclusion 
Young P. viridans are able to emerge from their egg sacs without 
the aid of an adult female (Group I and untilted egg sacs). The 
adult female Green Lynx opens and tilts her egg sac approximately 
six days prior to the emergence of young. The opening and tilting 
of the egg sac is the primary maternal care comprising emergence 
aid. Other maternal care exhibited by P. viridans includes pre- and 
post-emergence protection. 
Emergence of young from the lowest bowl/ lid juncture in tilted 
egg sacs and all directions from the bottom of the bowl in non- 
tilted egg sacs would seem to indicate that gravity may play a role 
in the site of egg sac exit by young Green Lynx Spiders. 
Emergence aid by an adult female made it possible for the young 
to emerge quicker than young where no emergence aid (tilting) was 
given. Tilting of the egg sac prior to emergence was in itself an aid 
but tilting of the egg sac was not a requirement for the young to 
emerge successfully. The adaptive significance of maternal care by 
the Green Lynx Spider is a higher percentage of young emerging 
from tilted egg sacs than from non-tilted. Although the number of 
young emerging was not documented, upon inspection of all the 
egg sacs cannibalism was in evidence in only the non-tilted egg 
sacs. Apparently the four extra days, on the average, spent in the 
non-tilted egg sacs resulted in cannibalism thereby reducing the 
percentage of young emerging from those egg sacs. No cannibal- 
ism was detected in the tilted egg sacs. 
The females of Group III not only adopted another female’s egg 
sac but opened and tilted their adopted egg sacs at the precise time 
they would have had they been their own eggs. These females 
would have opened and tilted their own egg sacs approximately 
12 days earlier but waited for what is most logically a cue from 
within the egg sac. The cue was most likely the activity of the 
new 2nd instar spiderlings. 
These findings are in contrast to those of Engelhardt (1964) who 
reported the maternal care exhibited by spiders of the genus Tro- 
chosa Koch (Lycosidae). He noted that like other lycosids Trochosa 
females must open the egg sac in order for the young to emerge 
successfully. The young are not able to hatch if the egg sac is 
opened too early. On the other hand, the egg sac must be opened 
no later than three days after the young have molted to the nymph 
