574 Surmullets, Croakers, etc. 
that of the parrot-fish, it is structurally different and must have 
been independently developed. Oplegnathus punctatus, the 
“stonewall perch” (ishigakidai), is common in Japan, as is also 
Fic. 468.—Opisthognathus nigromarginatus. India. (After Day.) 
the banded Oplegnathus fasciatus. Other species are found in 
Australia and Chile. 
The Swallowers: Chiasmodontide.—The family of swallowers 
Chiasmodontide, is made up of a few deep-sea fishes of soft 
flesh and feeble spines, the opercular apparatus much reduced. 
Fia. 469.—Black Swallower, Chiasmodon niger Johnson, containing a fish larger 
than itself. Le Have Bank. 
The ventrals are post-thoracic, the rays 1, 5, facts which point 
to some affinity with the Optsthognathide, although Boulenger 
places these fishes among the Percesoces. Chtasmodon niger, the 
black swallower of the mid-Atlantic, has exceedingly long teeth 
and the whole body so distensible that it can swallow fishes of 
many times its own size. According to Gill: 
“Tt espies a fish many times larger than itself, but which, 
nevertheless, may be managed; it darts upon it, seizes it by 
