GILL LIFE HISTORIES OF TOADFISHES 403 
a spine”’ which reminds one of “the venom-fang of a snake,” 
but is “less curved”’; “it has a longish slit at the outer side of its 
extremity, which leads into a canal perfectly closed and running 
along the whole length of its interior”; “a bristle introduced into 
the canal reappears through another opening at the base of the spine, 
entering into a sac situated in the opercle and along the basal half 
of the spine.”’ This spine is filled with “a fluid which becomes of 
a whitish substance of the consistency of thick cream” in specimens 
Fic. 115.—Thalassophryne maculosa. After Ginther. 
c 
preserved in alcohol; from the sac “on the slightest pressure,’ the 
fluid “freely flows from the opening in the extremity of the spine.” 
The spines of the dorsal, two in number, are also perforate, are slit 
in front of the tip, and “each has a separate sac” at the base with 
contents like the opercular sacs. “ Thus,” according to Gunther, 
“we have four poison-spines, each with a sac at its base, the walls 
of which are thin, composed of a fibrous membrane, the interior of 
which is coated over with mucosa.” 
The natural inference that this apparatus is of a poisonous nature 
is justified by what is known of the fish. The slightest pressure on 
the base of a spine causes the poison to jet a foot or more from the 
spine. According to John M. Dow (1865), “the natives of Panama 
seemed quite familiar with the existence of the spines and of the . 
emission from them of a poison’; this, “when introduced into a 
wound, caused fever, an effect somewhat similar to that produced 
by the sting of a scorpion, but in no case was a wound caused by 
one known to result seriously.” 
Three well-marked species have been attributed to the genus; 
one (7. maculosa) inhabits the Caribbean Sea about Puerto Cabello, 
a second (T. reticulata) the Pacific coast of Panama, and a third 
(T. dowt), distinguished by its elongate form, is a compatriot of 
the second. 
