TOAD-FISHES. 
133 
Fam KATRACHIDiE. 
Body tadpole-sliaped, posteriorly compressed , anteriorly terete with broad, fiat head. Scales small and cycloid. 
Eyes small, and directed more or less upwards. First dorsal fin short, with strong spinous rays; second dorsal 
long; anal similar in form to the second dorsal, hut shorter. Basal hones of the pectoral fin fiat in the external 
{distal) part, hut elongated, and anteriorly {in the proximal part) narrow a . Jaw-teeth of uniform size and pointed, 
set in a card, or some of them larger and obtuse. Vomer and palatine hones also furnished with numerous teeth. 
Lips fringed. Lateral line continuous or broken; the rest of the system of the lateral line and of the ? nuciferous 
ducts highly developed. Only three perfect branchial arches. Gill-openings confined to the sides in front of the 
pectoral fins. No pseudohranchice. Air-bladder more or less completely divided in a longitudinal direction, or 
broken up into two chambers with a communication between them. 
By the broad, flattened head and the loose, slippery 
skin, which is covered with extremely small scales or 
even naked, these fishes are placed in about the same 
relation to the Weevers as the Cottoids to the Scor- 
paenoids. We have further proof that the natural place 
of the Batrachoids in the system is by the side of the 
Weevers, not only in the arrangement of the fins and 
the other characters given above. Both these families 
have another common peculiarity in the poison organs 
which they possess. Gunther'' has described these or- 
gans in the genus Thalassophryne from Central America, 
which belongs to this family. They are situated, as 
in the Weever, on the operculum and in the spinous 
rays of the first dorsal fin, but are still more highly 
developed. The opercular spine is perforated, like the 
fangs of the true vipers, and not merely grooved, as 
in the Weever, the spines of which in this respect re- 
semble the fangs of venomous colubrine snakes. 
By the side of this poison organ in some Batra- 
choids is another, which, hotvever, belongs rather to 
the system of the lateral line and of the muciferous 
ducts, and the venomous properties of which are not 
yet fully demonstrated. The advanced development of 
the system of the lateral line is not confined to the 
head, with the usual, but numerous, branches, especially 
in the suborbital ring, where there is sometimes a row 
of pores hidden under a peculiar, longitudinal, dermal 
flap; but also extends to the trunk. This appears most 
distinctly in the genus Porichthys, from both the east 
and the west coasts of America, in which the pores of 
the lateral line, at least during youth, are especially 
distinguished by a golden-yellow, cornea-like substance 
in the openings. In this species the branches of the 
lateral line run, as usual, in graceful curves on the 
head and the middle of the sides, but also on the 
operculum and the branchiostegal membrane, as well 
as on the hover side of the lower jaw and on the 
belly itself, in curves which surround the ventral fins, 
ascend on the anterior side of the lobate base of the 
broad, pectoral fins, and surround the vent. Another 
branch slopes down from the axil to the lower part of 
the side, and then follows the base of the anal fin for 
some distance. Another branch of the lateral line, 
a dorsal canal, runs close to the base of the second 
dorsal fin. In the genus Batrachus, on the back of 
the pectoral fins, we find a row of pores from which 
oozes a slimy moisture, and in the axil of these fishes 
is a cavity beneath the skin, which in some species 
opens into a hole in the corner of the shoulder. The 
properties of the secretion formed in this cavity are 
not yet known; but Gunther 0 endeavours to explain 
it by a comparison with a similar structure in the same 
part of the body in certain Siluroids, where the poisonous 
properties of the secretion are more probable, as it is 
emitted at the base of the defensive weapons these fishes 
possess in the strong, serrated spines of the pectoral fins. 
The ventral fins of the Batrachoids are remarkable 
not only for their jugular position, but also for their 
“ In Batrachus Pacifici , the only species the skeleton of which I have been enabled to examine, I find 5 basal bones belonging to the 
pectoral fins, or one in excess of the ordinary number. The uppermost is narrow and terete, and has no rays of the pectoral fin articulating 
with it. The 3rd and 4th from the top are considerably narrower than the rest. The lowest of all is the largest and broadest. 
6 Proc. Zool. Soc. 1864, p. 155. 
c Introd. to Study of Fish, p. 192; Handb. Ichthyol., p. 129. 
