May II, iSSS.] 



SCIENTIFIC NEAVS. 



443 



Natural Utistor^* 



POISONOUS FISHES.— I. 

 The Weever. 



IT is a somewhat remarkable fact that poison, em- 

 ployed either as an offensive or a defensive medium, 

 is not met with among those which we generally term the 

 higher animals. The claws of the tiger, it is true, when 

 employed against a human foe, frequently cause symp- 

 toms which cannot be attributed to the mere laceration 

 of the flesh ; and the same is the case, although less 

 commonly, with the corresponding weapons of the lion. 

 But the results in question — lockjaw in fatal cases, and 

 a periodical re-opening of the wound in those in less 

 severity — cannot be traced to the operation of any actual 

 poison. The claws are not channelled or perforated, 

 neither are they furnished with venom-secreting glands. 

 And the strange after-effects which so frequently ensue 

 from the wounds which they cause are in all probability 

 due to a species of blood-poisoning, arising from their 

 frequent employment in tearing putrid carrion ; so 



deeply grooved along the edges, and each groove termi- 

 nates at the base of the spine in a conical cavity excavated 

 in the posterior edge of the bony part of the operculum. 

 In the sides of these excavations," he proceeds to say, 

 " the edges of the grooves lose themselves, so that there 

 is a perfect continuity between each groove and the 

 corresponding cavity. From the posterior edge of the 

 operculum the integument is continued over the spine to 

 within a very short distance of the point, by which 

 means the spine is enclosed in a complete sheath for 

 nearly its entire length, and the groove at each side is 

 converted into a perfect tube, extending from the conical 

 cavity at the base almost to the point of the spine. Yet," 

 says the Professor, in conclusion, " I have not been 

 able to detect any specific gland connected with this 

 apparatus." 



It is difficult, if not altogether impossible, to believe 

 that a structure such as this, so similar to that which we 

 find in the case of the venomous serpents, and in other 

 poison-bearing animals, does not fulfil corresponding func- 

 tions, more especially when we take into consideration the 

 consequences ensuing from the wounds which these 

 spines inflict. A mere prick from the " sting " of a 

 weever fish will cause the wounded limb to swell to 



The Weever (Trachinus Dracoj. 



that they become envenomed for a time, just as does 

 the dissector's scalpel, although not by the hand of 

 Nature. 



In birds we do not meet virith poison at all, in any 

 form or shape ; their weapons consist of talons and beak, 

 assisted, in a few exceptional instances, by the wings or 

 the legs. In the reptiles, however, we find that it is 

 present, first in one of the lizards (Hdoderma horriditm), 

 and afterwards in many of the snakes ; and in the fish 

 it is not at all infrequent, both in an offensive and a defen- 

 sive form. Among invertebrate animals it is common 

 enough. 



In many poisonous fish, however, is this strange pecu- 

 liarity, that the actual venom itself cannot be detected. 

 The weapon of transmission m.iy be channelled or per- 

 forated, as in the formidable spines of the Weever fish, 

 but no glands can be found in connection with them. 

 And yet it seems absolutely certain that some poisonous 

 medium is injected into the wound. 



This subject has received very careful attention from 

 Professor Allman, who expresses his firm belief, based 

 on long experience and investigation, that actual venom 

 is secreted, although he has not succeeded in finding 

 glands specially appropriated to such a purpose. " The 

 spmes in the gill-covers of the weaver," he says, " are 



nearly double its size, while the dull, throbbing pain, 

 which is often most severe, will continue for days, and 

 even weeks afterwards. If the recipient be already in 

 feeble health, death itself may very possibly follow. And 

 so well known are the powers of the fish that, both in 

 France and in Spain, the removal of its dorsal fin and 

 the hinder portions of the gill covers is rendered obliga- 

 tory immediately upon capture, in the former country 

 by police regulation, and in the latter by statutory 

 law. 



It were idle to assert that results such as those de- 

 scribed could be due to a mere insignificant puncture, 

 no more alarming in itself than the prick of a moderately 

 large pin. Yet the fact remains that no actual poison 

 has been or can be detected, either in the spines them- 

 selves, or in the cavities at their roots. Professor All- 

 man, it is true, states that in each of these cavities is a 

 small pulpj' mass, which may or may not be glandular 

 in character ; but he evidently inclines to the latter 

 belief. He also suggests that the virus may possibly be 

 secreted by the pulpy sheath of the spine ; but this, as 

 he himself admits, is nothing more than mere conjecture. 

 And the question at present stands over for solution by 

 some future investigator. 



{To be continued.) 



