(2) During her Iifetime, the female black widow produces several round,
cream-white egg sacs with an average of some 200 eggs within each. These sacs are
attached to the spider's web. The eggs hatch In 2 to 4 weeks into tiny, active, young
spiders. The eggs are usually laid during the summer and the young reach maturity the
following spring. These spiders are found on the undersides of outhouse seats, in piles
of lumber and trash, and in empty cans and buckets. They are frequently found
beneath houses and in storerooms and garages. The web is recognized as it is usually
extremely irregular, very loosely woven, and has a ragged appearance. In addition, the
tube into which the female retires is not in plain view. Black widows Iive in dark areas
and generally avoid Iight. Their normal food is insects and they are usually not
aggressive, unless they are agitated or hungry. When guarding her egg sac, the female
is particularly prone to bite.
(3) The bite of the female black widow spider is not always felt, and often
there is Iittle visual evidence except for slight swelling and two tiny red spots at the bite
site. CIinical cases are characterized by severe muscular pain, a rigid abdomen,
tightness in the chest, and difficulty in breathing that may (in 6 to 6 percent of untreated
cases) result in death. Although very young chiIdren or the very aged are the most
susceptible to black widow spider venom, they are rarely bitten. Bites in the genital
area and buttocks have commonly occurred while using outhouses. The majority of
deaths have occurred among migrant workers in the California vegetable fields. The
male black widow spider has very Iittle venom and the mouthparts are not sufficiently
strong to penetrate the skin of people.
b. Brown Recluse Spider, Loxosceles reclusa. See figure 1-2. The brown
recluse spider is found in South, Central, and North America.
(1) This spider is of medium size, with body measuring about 7 to 10 mm
long and about 3 to 6 mm across. The body color varies from Iight fawn to dark brown.
The most distinguishing characteristics are the dark fiddle-shaped mark on the anterior
portion of the cephalothorax and six eyes in three pairs. The young resemble the
adults. There are eight molts in the development to the adult stage; sometimes this
development takes as long as 200 days. Indoors, these spiders are commonly found in
houses and associated buildings, boiler houses, schools, churches, Iibraries, stores,
and other such buiIdings. In outdoor locations, it has been found beneath flat rocks,
under loose bark, in crevices of old decaying logs, and in trash piles.
(2) Experiments with the venom of the brown recluse spider have shown
that both sexes are capable of inflicting poisonous bites to mammals. This is unlike the
black widow in which only the female is dangerous to humans. The symptoms following
a bite by the brown recluse are quite unlike the typical symptoms of the black widow
bite. Following a bite by the brown recluse, the typical reaction in humans is necrosis
(kilIed tissue) at the site of the bite. The victim may not be aware of being bitten for 2 or
3 hours, or a painful reaction may occur immediately. A stinging sensation is usually
followed by intense pain. A small blister usually rises and a large area around the bite
becomes inflamed and swollen. The patient may become restless, feverish, and have
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