Shelob or Charlotte?

This silhouette on the window screen caught my eye this morning -- a very large spider sitting on a very large egg sac.

Spiders are something lots of folks react to about like they do to snakes. Take J.R.R. Tolkien's Shelob in the second of The Lord of the Rings trilogy,The Two Towers:

"But still she was there, who was there before Sauron, and before the first stone of Barad-dûr; and she served none but herself, drinking the blood of Elves and Men, bloated and grown fat with endless brooding on her feasts, weaving webs of shadow; for all living things were her food, and her vomit darkness."

Harsh words -- and mighty effective. But then there's E.B. White's Charlotte from the beloved Charlotte's Web.

"It's a perfectly beautiful egg sac," said Wilbur, feeling as happy as if he had constructed it himself.
"Yes, it is pretty," replied Charlotte, patting the sac with her two front legs. "Anyway, I can guarantee that it is strong. It's made out of the toughest material I have. It is also waterproof. The eggs are inside and will be warm and dry."

I don't know what this brooding mama is --maybe a Wolf Spider ? She doesn't have a web so I needn't expect messages. I wouldn't try picking her up as many spiders, not just Black Widows and Brown Recluses, have bites that can be painful. But I like looking at her as she regards me with her multiple eyes.

Is she a Shelob or a Charlotte -- or just another of nature's wonders?