From the general prportions of the body and the distinct impression that we are dealing with a fish, I suspect we are looking at a slightly distorted depiction of an Atlantic sturgeon, of the same species that recently made news again as a "Sea Monster" washed up in South Carolina. The species has a record greatest length of fourteen feet and is also suspected as the culprit in some Loch Ness Monster sightings-probably even a few reported as much this size and shape. If the nose end was poked up free of the water at some time during swimming, it might have presented such an appearance and it could even have shown its pectoral fins in about the location where they are depicted in the drawing. Furthermore, it would have about a dozen small knobs on its back as described (although the drawing only shows six) and would give good reason to depict the body as being scaly over all.
The shape of the top of the head and the position of the eye is a good match but the mouth is drawn wrongly for a sturgeon. I surmise the head was seen from the top and side rather than from below where the shape of the mouth could have been made out. The neck in the drawing is wrong for the fish but I can see where an inexperienced viewer might assume that it "Needed" to have a neck like that. And the shape of the tail is wrong but even depicting a fish's tailfins is close enough to give reason to assume it might have been a sturgeon.
In this case even if the exact report the drawing is meant to go with is not certain, it definitely solves another mystery. In 1833 Robert Bakewell, the British Geologist, suggested in the fourth edition of the Introduction to Geology that the sea-serpent might be a form of ichthyosaur, citing a report "by an American Captain" which said the Sea-serpent had a body as big around as a cask, paddles like a turtle and a head like a crocodile, which is a fair description of this picture. Heuvelmans says in a footnote that he does not know which report Bakewell refers to. (IN THE WAKE OF THE SEA-SERPENTS p. 182) The drawing is credited to the journal Isis. That would also be why the subsequent report by the yacht Princess (1875, p265-266) identifies the creature observed as an "Ichthyosaur" although it is more likely a kind of a whale.
Rupert T Gould suggested that some of the Massachussets Bay Sea-Srpent reports might be mistaken views of a gigantic sturgeon, but he said that as a joke. It now seems likely that it was not so much of a joke after all.
http://news.discovery.com/animals/marine-monster-mystery-120328.html
MARINE MONSTER MYSTERY ON S.C. BEACH
Analysis by Benjamin Radford
Wed Mar 28, 2012 09:54 AM ET
A bizarre creature that washed ashore last week in Folly Beach, S.C., sparked speculation in the area and on the Internet that a dead sea monster might have been discovered.The tan-brown animal with greenish patches was strange enough, but what really baffled beachgoers was its massive size and the dinosaur-like bony plates on its sides. It's not clear just how long it was, but photos suggest it exceeded 10 feet.
Like many washed-up carcasses it carried both a salty stench and an air of mystery. Speculation ran rampant, with commenters suggesting that the creature was everything from a dinosaurian sea monster to a toxin-spawned mutation to a chupacabra.
Scientists, however, were somewhat more skeptical.
VIDEO: BIZARRE OARFISH FILMEDOne of the first to identify the monster was Dr. Shane Boylan of the South Carolina Aquarium. Two big clues allowed Boylan to identify the fish more or less immediately: the animal's shape and distinctive bony plates.
The marine monster was in fact an Atlantic sturgeon. Part of the reason the giant fish's identity was difficult to determine is that sturgeon are not normally the strange brownish tan color but instead lighter colored and silvery. The South Carolina monster's flesh color had changed as it baked in the sun. The dinosaur identification was actually pretty close to accurate; sturgeon are among the oldest bony fish in existence.
It's not surprising that the sturgeon scared and confused people; Atlantic sturgeon have been known to reach 15 feet long and weigh over 500 pounds; seeing the beasts close-up is not for the faint of heart.
PHOTOS: SEA MONSTERS REAL but it is protected by scales of a silvery gray color."
Though often claimed as an eyewitness report of "America's Loch Ness Monster," his description is clearly that of a sturgeon-like gar fish.
Another reason that the sturgeon seemed monstrous was that it's an unusually large fish.
The fish most people (and certainly most urban dwellers) encounter are relatively small -- goldfish perhaps, or aquarium fish. Sport fishermen, butchers and marine biologists are far more likely to recognize large fish such as tuna, sturgeon and gar, for example, which often grow to surprising sizes.
Even seeing large fish on television, in aquariums or in photographs does not necessarily prepare city-dwelling beachgoers for real-life encounters with a beached, smelly giant.
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