— i ania aa 
STRENGTH OF WEBS AND POWER OF SPIDERS. 239 
where it shows as a tissue of close texture. In the building of additions 
to the web, however, the new part shows as a quite open plane of 
mesh work,! 
The webs of Medicinalis are often built in the angles of cellar 
windows, along the sill, and in positions quite similar to that in which 
Strength the Batavia snake was caught. The strength of several snares, 
of Web, 10Und in the cellars of the Academy of Natural Sciences of 
Philadelphia, was tested as follows: two webs bore up under 
a pencil weighing sixty-eight grains; several small webs bore a weight 
of one-fourth and one-half ounce in corks spread over the surface, but 
Fig, 221. The pouch, web, tower, and cocoon of the Medicinal spider, Tegenaria medicinalis. 
broke down under an equal weight condensed into a small shell. One 
web bore up easily, and apparently would have carried for an indefi- 
nite period, the half ounce shell. It also sustained for a short period 
a weight of one ounce, and then gradually gave way by the breaking 
down of the thread attachments to the wall, without any yielding of 
the sheet itself. 
The weight of a “striped snake,” such as is alluded to, probably 
our common garter snake, Eutenia sirtalis, Linn., is accurately fifty-five 
‘The two webs (Fig. 221) measured: No. 1 (upper), 14 inches long across the hypothe- 
nuse, by 10 inches deep; No, 2 (lower), 18 inches long across the sheeted part, 24 inches 
across the meshed extension, depth 9 inches. 
