Over all treatments, twenty females produced an egg sac
(Table 4); no female produced two or more egg sacs
These spiders were starved under dark conditions until some of them had spun webs and shed their egg sacs
into the cups.
This provided basic biology information that benefitted research involving insecticide bioassays on brown widow egg sacs
(Vetter et al, in prep); knowing the phenology of seasonal clutch size helped determine whether lab-produced egg sacs
would be temporally comparable with natural oviposition and, hence, whether pesticides tested on egg sacs
would have real world relevance.
3 shows the black widow spider with its egg sacs
Despite the fine netting over the box to prevent spiderling escape, during the night before May 20th, spiderlings from the first egg sac
disappeared from box 1 and left the laboratory.
"It now has five egg sacs
, each containing 500 to 750 eggs," he said.
A few days later she found a dead spider and an empty egg sac
on them and soon afterwards she started finding the tiny, fast-moving creatures on her curtains and walls.
Emma said: 'One egg sac
can produce up to 400 spiders.
There may always be an egg sac
waiting to release an egg.
The female hunting spiders, such as the wolf spider, carry a large egg sac
around under their abdomen wherever they go and, once hatched, the young cling on and are carried everywhere for weeks, operating nocturnally, they hunt crawling insects relying on their own speed and size to gain their prey.
3B, where the proembryo was multicellular and the endosperm nuclei multiplied and were more or less evenly spaced in the egg sac
extending from the proembryo to the hypostase.
She guards them in an egg sac
made from her spider silk.