i 4 i N A T U R A L H I S T O R Y of N R TV A V. 



on each fide, and looks like a crefcent. The tail is quite even 



at the end, and refembles a birch broom cut tranfverfly : along 



the back runs a fmall undulated ridge, and under the belly is a 



piece of foft fpungy excrefcence, with which it fticks faft to the 



rocks like a fnail ; and it requires fome ftrength to get it loofe. 



The female, or Rogn-Rexe, is fomething larger than the Rogn- 



Kalen, or male, and of a blue colour. They ejecl: their (pawn 



in large quantities about Whitfuntide : hence the Filh has its 



Norvegian name. - The fatter it is the more it approaches to a 



red colour, being otherwife greenilh. The body, as I ohferved 



before, is but fmall, and, as I am informed, very delicate food, 



for I have never tafted it. The Otter is very fond of this Fifh, 



and it often falls a prey to him. As the Rogn-Kallen never bites 



at any bait, and loves deep water, it is feldom caught but by 



accident in the Cod or Salmon nets. When they are feen 



fwimming near the furface of the water the fifhermen often give 



them a blow on the neck with their oar, and fo take them ; but 



they are only ufed as a bait for other Filh;, particularly the 



Turbot, who is very eager after them. 



Rokke. Rokke, Rokke filk, the Thornback, Raia Clavata, in Norway 



called Skate. 'Tis a Sea-fifh of an extraordinary fhape, and not 



unknown in Denmark, tho' it feems to differ a little from 



ours * y for there are various forts, all which, or moft of them, 



are defcribed by Willoughby, Lib. iii. c. vii. p. 68, & fequ. 



The Norvegian Skate in body is, like a large Flounder, quite 



flat, with a fharp head: it is white under the belly, and 



of a darkifh brown on the back ; and has prickles and fmall 



circles on the fkin. There are leverai broad fins projecting out 



on each fide of this Fifh, like wings, larger than its whole body. 



But what is moft remarkable, is a roundifh tail, of about two 



foot long, full of angular knobs. The mouth is not placed, as 



in other Fifties, in the head, but underneath, fomething like that 



of the Shark; befides, it has this in common with that Fifh, 



namely, that it has no bones, but is of the cartilaginous kind. 



It has pretty large eggs, from which its young are produced at 



a proper time. The liver is large and fat, and yields a good 



deal of train oil, which is the chief thing the fifhermen catch it 



for : it is feldom eaten here, tho' fbme people firft dry, and then 



export them. They are generally caught with a hook and 



line. 



* Earum alias funt lasves, alias afperas. Lasvium alias ftellatas, alias non. _ Afpera- 

 rum alias magis alias minus tales. Magnitudine inter fe differunt. Bicubitales ali- 

 quando vidit Salvianus. Gaip. Schott. Phyf. curiofa, Lib. x. c. 40, 



SECT. 



