THREE CRUISES OF THE BLAKE." 
Fig. 206. — Plectromus suborbitalis. 1. (U.S. F. C.) 
The snappers and groupers of the tropics surely range below 
one funnel fathoms, but it seems hardly appropriate to regard 
any of the true percoids, or any of their very near allies, as 
really abyssal in habit. 
Some of the scombroids seem to inhabit deep water, espe- 
cially the Trichiuride, the so-called cutlass-fishes, which may 
be considered a deep-sea group. They are long, compressed, of 
glistening silver color; they date back to the chalk of Lewes 
and Maestricht, and occur in the eocene schists of Glaris. A 
number of pelagic scombroids have been taken under such 
circumstances as to render it probable that they descend to 
considerable depths. The lumpsuckers (Liparidz) are well rep- 
resented by four genera, which have undergone extreme modifi- 
cations characteristic of abyssal forms. They have soft, cavern- 
ous skeletons, immensely developed mucous canals, and are soft 
and flaccid in the extreme. The family of lump-fishes (Cyclop- 
teride) is represented below the hundred-fathom line off the 
Atlantie coast. 
The “ ribbon-fishes” may be named with the abyssal groups, 
although they have never been dredged at any considerable 
depth, but are known solely from individuals stranded upon the 
shores or found at the top of the water. The largest of the 
ribbon-fishes 1s capable of rapid motion at the surface, and is 
probably the animal which has most often been taken for the 
sea-serpent. The * Bermuda sea-serpent," Regalecus Jonesii, 
was seventeen feet long, and swam with great velocity through 
the surf, and dashed itself upon the shore. It seems altogether 
