1982] Ross , Richman, Mansour, Trambarulo & Whitcomb 301 
required approximately 4 hours and began with assistance from a 
pair of brownish “egg teeth” positioned on the patellar region of 
each pedipalp. The chorion was split anterioventral to the leg region 
with swelling pulses (30-60 seconds between pulses and 2-3 pulses 
per set) to about 2/3 of the diameter of the embryo. The membranes 
were drawn towards the spinnerets by an alternating combination 
of abdominal contractions and withdrawal movements of the legs, 
similar to those observed in molting. The shed membrane remained 
attached to the spinnerets until it was discarded at the beginning of 
the second postembryonic stage along with the vitelline membrane 
surrounding the legs. The first postembryonic stage lasted from 1-2 
days for four egg masses, but four other egg masses required 5-6 
days to become second postembryos (total n = 8). 
During the second postembryonic stage the specimens were rela- 
tively quiescent. Eye pigment began to appear about the fifth or 
sixth day of the second postembryonic stage, with markings around 
the carapace margin and on the abdomen becoming visible soon 
afterwards. Dark setae appeared shortly before the first molt 
occurred. The duration of the second postembryonic stage was 9-10 
days (n = 3). The first instar spiderlings remained in the egg sac 
approximately one week before emerging. One female which mated 
on the 28th of March, 1980, produced an egg sac 12 days later. 
From this egg sac 277 first instar spiderlings emerged after 32 days. 
All of the longevity data came from this group of spiderlings. 
The duration of each instar is summarized in Table 1 . Males were 
more likely (as noted by Bonnet 1932) to have one or two fewer 
molts than females, but this was not an absolute rule. Sekiguchi 
(1945) recorded complete data for only one female H. venatoria and 
found a total of 1 1 instars. He, however, apparently included the 
second postembryo as the first instar. Of the adults in our study for 
which complete data are available, the males (n = 3) had 8-10 
instars (X = 8.7, SD = 1 .2) which lasted 241 .7 days (SD = 56.2) and 
the females (n = 13) had 9-12 instars (X = 10.6, SD = 1.0) which 
lasted 315.6 days (SD = 21.0). The survival rate from first instar to 
adult in the laboratory was approximately 85%. Total length of life 
from egg to death for our laboratory reared specimens was for males 
(n = 4) 355-586 days (X = 464.5 days, SD = 1 12.0) and for females 
(n = 16) 298-710 days (X = 580.3 days, SD = 128.6). Rovner (per. 
com.) found that some females of H. venatoria can survive for three 
years as adults in the laboratory. 
