1972] 
Fergusson — Hypochilus thorelli 
195 
sac was on a section of rock covered with gray lichens ; this sac was 
covered with gray lichens. No covering is put on the sac when it 
is attached to a bare rock or one covered with white crustose lichens. 
The sacs are attached some distance away from any webs, though in 
the same microhabitats, and the females do not guard them after they 
are completed. 
I have records (field notes) for 48 single egg cases, 12 records of 
2 cases attached together, and 1 record of 3 together. Not all of 
these were collected, however, so I have records of egg numbers for 
only 1 pair (50 and 103 eggs) and for the single instance of 3 sacs 
attached together (45, 81, and 92 eggs). The mean for 25 single 
egg sacs examined was 74.4 eggs; range 31-109. Eggs are whitish 
and spherical, measuring about 1.10 mm in diameter (mean of 25 
eggs measured after 2 days in 80% ethanol; range 1. 07-1. 15 mm). 
I was unable to determine the number of egg sacs constructed per 
female. Presumably when two cases are attached at the same place 
on the rock face, they were deposited by the same female. Females 
were observed with incomplete egg cases (lacking camouflage) on 
9 September, 28 October, 21 and 22 November. In all instances the 
cases were sealed up and attached by a single strand. 
Life History 
Postembryonic development. Egg sacs are deposited from Septem- 
ber through November. The winter is spent in the egg stage, with 
eclosion occurring in the spring. One sac containing “prelarvae” 
(see below) was collected on 6 March (elev. 700 m), but until 20 
April, all others collected still contained only eggs. Twelve sacs 
were collected on 27 April in the Nantahala Gorge (elev. 600 m) ; 
all of these still contained eggs. 
In H. thorelli , there appear to be five instars between eclosion and 
dispersal from the egg sac. (I determined these by examination of 
preserved egg sacs collected from March through May.) After the 
terminology of Vachon (1957), there are two prelarvae, one larva, 
one prenymph, and one nymph. The nymph is the active stage (about 
2 mm in total length) that emerges from the egg sac and constructs 
a web. Hereafter nymphal stadia will be referred to as spiderlings. 
Dispersal and first web. Spiderlings were first found out of the 
egg sac on 25 May. Many of these were still within the opened 
egg sac. Those that were out of the sac were on the adjacent rock 
face. Silk was present where the spiderlings had gathered, but no 
definite webs were visible. The sac involved had been marked on 
