Smithsonian miscellaneous collections . spines. ThehoUowad opercular and dorsal spines are connected with spe-cial glands at their bases. The species of Thalassophryne havea distinctly developed poison apparatus, to some extent analo-gous to that of the weevers, first elucidated by A. Giinther(1864). As just noted, there are hollowed spines to the oper-cle as well as to the dorsal fin. The operculum is very narrow,verticallv stvliform, and verv mobile; it is armed behind with ] life histories of toadfishes 403 a spine which reminds one of the venom-fang of a snake,but is less curved ; it
Smithsonian miscellaneous collections . spines. ThehoUowad opercular and dorsal spines are connected with spe-cial glands at their bases. The species of Thalassophryne havea distinctly developed poison apparatus, to some extent analo-gous to that of the weevers, first elucidated by A. Giinther(1864). As just noted, there are hollowed spines to the oper-cle as well as to the dorsal fin. The operculum is very narrow,verticallv stvliform, and verv mobile; it is armed behind with ] 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 sht at the outer side of itsextremity, which leads into a canal perfectly closed and runningalong the whole length of its interior ; a bristle introduced intothe canal reappears through another opening at the base of the spine,entering into a sac situated in the opercle and along the basal halfof the spine. This spine is filled with a fluid which becomes ofa whitish substance of the consistency of thick cream in specimens. Fig. 115.—Tlialassophrync maculosa. After Giinther. preserved in alcohol; from the sac on the slightest pressure, thefluid freely flows from the opening in the extremity of the spines of the dorsal, two in number, are also perforate, are slitin front of the tip, and each has a separate sac at the base withcontents like the opercular sacs. Thus, according to Giinther, we have four poison-spines, each with a sac at its base, the wallsof which are thin, composed of a fibrous membrane, the interior ofwhich is coated over with mucosa. The natural inference that this apparatus is of a poisonous natureis justified by what is known of the fish. The slightest pressure onthe base of a spine causes the poison to jet a foot or more from thespine. According to John M. Dow (1865), the natives of Panamaseemed quite familiar with the existence of the spines and of theemission from them of a poison ; this, when introduced into awound, caused fever, a
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Keywords: ., bookauthorsm, bookcentury1800, bookdecade1860, booksubjectscience
