SOFT-SPINES AND FROG-FISHES. 
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trunk and fourteen tail-vertebra). The body is elongated, and covered with very 
small scales; the mouth has very thick lips; and the premaxillse have a large 
tooth behind. The dorsal fin is single, and, like the anal, greatly elongated; 
its anterior portion having a few simple rays. There is one spine to the five- 
rayed pelvic fins; and the gill-membranes are united beneath the throat, the gill- 
cover being armed with a spine. Of the three tropical species constituting this 
genus, the one here figured (M. lioedti) is distributed through the Indian and 
Pacific Oceans, from Mauritius to the Sandwich Islands; the second has a nearly 
similar range; but the third is found on the Atlantic coast of Tropical America, 
Frog-Fishes Frog-fishes ( Batrachus ) may be taken as our representatives of 
the second of the two families under consideration. The family to 
which they belong is characterised by the distinct spinous portion of the dorsal 
fin, which includes a few pungent spines; while the pelvic fins have one spine 
and only two soft rays. The head is broad, thick, and frog-like; the body 
hcedt's soft-spine (2 nat. size). 
elongate, and compressed behind; and the skin either completely naked, or 
covered with small scales; the conical teeth being of small or medium size. The 
soft dorsal and anal fins are elongated, and the pectorals simple; the rather 
narrow gill-opening forming a more or less nearly vertical slit in advance of the 
latter, and the opercular bones being armed. An air-bladder is invariably present. 
All the members of the family are of small size and carnivorous habits, living on 
the sea-bottom and often ascending tidal rivers; but, while the majority are 
confined to the tropics, a few range into the warmer parts of the temperate zones. 
As a genus, the true frog-fishes are characterised by the spinous portion of the 
dorsal fin having three strong spines, and the presence of several spines on 
the gill-cover; while in many species the margins of the mouth, as well as other 
parts of the head, are provided with shining tentacles. Out of about a dozen 
species, one ( B. didactylus ) occurs in the Mediterranean. Some of the species 
have a poison-gland under each pectoral fin ; and at Penang all the tribe are 
regarded as highly poisonous, although in Bombay their flesh is eaten by the 
poorer classes of natives. The poison-gland attains its highest development 
