Your Mystery of the Night

Look very closely at the below picture. Do you see it? Not the female, (the lady) crouching over, nor the dog. The big white blob:

This washed up on St. Cyrus, a beach about 100 miles (160 km) north of Edinburgh
This washed up on St. Cyrus, a beach about 100 miles north of Edinburgh.

Yes, it is naval and yes, you have eaten it. Although, not recently. (What with all the Mayor Doombergs around. . .) Mmm, delicious.