thornbacks

"thornbacks" who would try to pass for the desired age:

Customs and Fashions in Old New England Alice Morse Earle 1881

Besides bass, we took plenty of thornbacks, and an abundance of lobsters, so that the smallest boy in the plantation may both catch and eat as many as he may wish of them.

Colonial Children 1902

Here are also skates, thornbacks, and other fish of the ray kind

Early Australian Voyages: Pelsart, Tasman, Dampier John Pinkerton 1792

They saw a large turtle, and many skates and thornbacks, but caught none.

Early Australian Voyages: Pelsart, Tasman, Dampier John Pinkerton 1792

Here are also skates, thornbacks, and other fish of the ray kind

A Voyage to New Holland William Dampier 1683

They saw a large turtle and many skates and thornbacks, but caught none.

A Voyage to New Holland William Dampier 1683

Plus some bigger thornbacks, whiting and rough hounds - a small shark that usually gets called rock salmon at the chippy because no one would eat a rough hound.

The Guardian World News Stephen Moss, Sam Wollaston, Laura Barton, Tim Dow 2010

And four boxes of thornbacks, which may fetch £350.

The Guardian World News Stephen Moss, Sam Wollaston, Laura Barton, Tim Dow 2010

Arimanian demon; being thus in devotion for their kind friends and relations that transformed them into birds, whether when they were maids, or thornbacks, in their prime, or at their last prayers.

Gargantua and Pantagruel, Illustrated, Book 5 Fran��ois Rabelais 1518

After this S. Austin entered into Dorsetshire, and came in to a town whereas were wicked people who refused his doctrine and preaching utterly and drove him out of the town, casting on him the tails of thornbacks, or like fishes, wherefore he besought almighty God to show his judgement on them, and God sent to them a shameful token, for the children that were born after in that place had tails, as it is said, till they had repented them.

The Golden Legend, vol. 3 1230-1298 1900