External gills usually contains muscle tissue, and may be moved by the animal as a free appendage, in order to stir up stagnant water. The stalk is lined by many thinly walled filaments (fimbriae), containing the majority of blood vessels used in gas exchange. Animals usually have one external gill originating on each gill arch (except the hyoid), which leads to there being three pairs of external gills in salamanders, and four in the gilled larvae of lungfish. External gills External gills are the gills of an animal, most typically an amphibian, that are exposed to the environment, rather than set inside
Puzzled Pint is a not-for-profit, volunteer-run event, with a goal of introducing new players to the world of puzzlehunts. The emphasis is on the casual nature of the evening. The puzzles are not as advanced or numerous as day-long or weekend puzzle events, and hints are always free. An archive of all previous puzzles is on the website and available under a flexible Creative Commons license so that they may be repurposed for other events and activities. Puzzled Pint has had a theme every month since September 2010. The first two months had puzzles with no common theme. Puzzled Pint Puzzled Pint