332 FISHES. 



observations of E. P. Wright, some of the species at least live 

 at a considerable depth, perhaps at a greater depth than any 

 of the other known Sharks. The Portuguese fishermen fish 

 for them in 400 or 500 fathoms with a line of some 600 

 fathoms in length. The Sharks caught were specimens of 

 Ceiitropliorus coelolepis, from three to four feet long. " These 

 sharks, as they were hauled into the boat, fell down into it 

 like so many dead pigs ; there was not the smallest motion of 

 their bodies. There can be no reasonable doubt that they 

 were inhabitants of the same great depth as Hyalonema" and 

 that, in fact, they were killed by being dragged to the surface 

 from the pressure of water under which they lived. The 

 dermal productions of some of the species have a very peculiar 

 form, being leaf-shaped, pedunculate, or ribbed, or provided 

 with an impression. 



Spinas. — Each dorsal fin with a spine. Teeth of the lower 

 jaw with the point so much turned aside that the inner margin 

 of the tooth forms the cutting edge. Upper teeth erect, each 

 with a long-pointed cusp and one or two small ones on each side. 

 Spiracles wide, superior, behind the eye. 



Three small species from the Atlantic and the southern 

 extremity of America. Centroscyllmni is an allied genus 

 from the coast of G-reenland. 



ScYMNUs. — Two short dorsal fins without spine, the first at a 

 considerable distance from the ventrals. Dermal productions 

 uniformly small. Nostrils at the extremity of the snout. Upper 

 teeth small, pointed ; lower much larger, dilated, erect, triangular, 

 not very numerous. Spiracles wide. 



A single species, S. lichia, is rather common in the 

 Mediterranean and the neighbouring parts of the Atlantic. 



Lemaegus. — All the fins small ; two dorsal fins, without 

 spine, the first at a considerable distance from the ventrals. 

 Skin uniformly covered with minute tubercles. Nostrils near 

 the extremity of the snout. The upper teeth small, narrow. 



