The hag, like the lamprey, lacks paired fins and fin rays. Its skeleton is wholly cartilaginous, without bones, its mouth is jawless; and its skin is scaleless. It is easily recognized by its eel-like form; by its single finfold (a fold of skin, not a true fin) running right around the tail and forward on the lower surface of the body with no division into dorsal, caudal, and anal fins; by the single gill pore on each side, just forward of the origin of the ventral finfold; by its lipless mouth, star-shaped in outline when closed; by the single nasal aperture at the tip of the snout; by its peculiar barbels or “tentacles,” two flanking the mouth on either side and four surrounding the nostril; and by the evertible tongue studded with rows of horny rasplike “teeth.” Being blind, it doubtless finds its food by its greatly specialized olfactory apparatus. It feeds chiefly on fish, dead or disabled, though no doubt any other carrion would serve it equally well.
It is best known for its troublesome habit of boring into the body cavities of hooked or gilled fishes, eating out the intestines first and then the meat, and leaving nothing but a bag of skin and bones, inside of which the hag itself is often hauled aboard, or clinging to the sides of a fish it has just attacked. It is only too common in the Gulf of Maine; perhaps it is not absent there from any considerable area of smooth bottom.
From Fishes of the Gulf of Maine by Bigelow and Schroeder (1953) online courtesy of MBL/WHOIhttp://www.gma.org/fogm/Myxine_glutinosa.htm
Al Bezanson
Good Morning Gloucester 
I never heard about this one learn a new thing everyday! 🙂 Dave
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Dave, you may not want to read on further. Guess where our local hagfish have a market.
Al
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In New England, a growing fishery for Atlantic hagfish (Myxine glutinosa) has initiated science and
policy discussions about the development of the fishery, its potential for future expansion, and its effect
on the resource. The hagfish fishery in New England was developed in the early 1990s, with the first
reported landings of around 1 million pounds in 1993. Korean buyers quickly recognized that a fishery in
the New England area could provide the high quality hagfish skins used in making leather as well as
hagfish meat for human consumption.
Click to access hagfish.pdf
Al Bezanson
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Sir, Thanks Schooner 39 now we have come full circle for me it’s listen and learn here! I was over here and didn’t even know the why in the open fish markets this way! We have a four day market today big one and some are open daily regardless of weather typhoon exception. V/r
Dave
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Here’s more about hagfish for Dave M …… They call them ‘slime eels’ around here, although they really are not slime eels. We have a different beautiful fish (simenchelys parasiticus) by that name.
https://news.nationalgeographic.com/2017/07/hagfish-slime-oregon-highway/#close
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Ahoy Dave M ….. Can you give us a report from over there in Korea on the tastiness of hagfish?
Al Bezanson
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