FISR POISONING AND POISONS.— HAMLYN-HAERIS AND SMITH. 7 



3,000 parts of water. This in conjunction with the slow effectivity of Terminalia 

 sericocarpa (8 per cent, tannin) and Eucalyptus species (6 per cent.) in which 

 no other principle likely to be toxic could be discovered, and the innocuity of 

 material free from tannin, warrants us in the conclusion that materials containing 

 tannin in relatively small percentage are efficacious in use but that their efficacy 

 depends on their employment in relative abundance, as indeed is indicated by 

 the notes of observers relating to the use of Eucalyptus and Acacia species/^ '^ 



The identification of sapotoxin as the active principle of Careya, Cupania, 

 Faradaya, and Garcinia, of derrid in indigenous Dcrris species, and the indication 

 of tephrosin in TepUrosia rosea and T. purpurea, serves to indicate the extreme 

 potency of these materials, here as elsewhere due to these principles, and is 

 presented also as a contribution to the pharmacology of the indigenous flora. 



Our observations lead us to adopt a classification, based on efficiency, of the 

 fish-poisons investigated by us, as follows : — 



Group A.^ — Effective and rapid in action at great dilution. — Derris, 

 TepUrosia. Pongamia, "Nero," containing active principles 

 associated with ether-soluble resins. The sapotoxin-containing 

 Careya, Cupania, Faradaya, Garcinia. 



GrBOUP B. — Poisons of intermediate effectivity. — Barringtonia speciosa. 

 Stephania hernandicefolia, alkaloid-containing. 



Group C. — Poisons of lesser effectivity. — Slow in action at higher con- 

 centrations or uncertain in action. Acacia, Albizzia, Eucalyptus, 

 Tliespesia., Terminalia, Polygonum. 



Group D. — Reputed poisons, found innocuous. — Sarcocephalus, Pleio- 

 gynium, Petalostigma, Alocasia, Asclepias ( f). 



Identified species recorded elsewhere, not examined by us : — 

 Acacia salicina, var. varians (Maiden), N.S.W. ; 

 Acacia falcata (Maiden), N.S.W. ; 

 Acacia penninervis (Maiden), N.S.W.; 

 Acacia verniciflua (Lauterer), Bathurst; 

 Acacia salicina, Roth. 

 AdcnantJiera ahrosperma (Roth) ; 

 Bauhinia sp. (Ewart and Morrison), N.T. ; 

 Barringtonia racemosa (Palmer) ; 

 Derris scandens (E. J. Banfield) ; 

 Eucalpytus resinifera (Roth) ; 



Eucalyptus corymhosa (IMathews), Western Australia; 

 Galactia varians (Roth) ; 

 Luff'a cegyptiaca (Palmer) ; 

 Melia composita (Roth) ; 

 Tephrosia astragaloides (Roth) ; and 

 Acacia auriculiformis (seeds), on the authority of G. F. Hill, Darwin. 



^ 11^ Greshoff (13) recognising the effectivity of tannin-containing materials, follows Claude 

 Bernard in ascribing to tannic acid an astringent effect and interference with the ftinction of 

 the gills (p 35). 



