v] Polygonaceae, Thymelaceae 65 



Water-pepper to have caused hsematuria; fatal results have followed. 

 Pott records similar symptoms. In regard to Persicaria it should be 

 noted that it varies considerably in general form, and may possibly 

 vary also in acridity. Bentham and Hooker state of P. hydropiper 

 that "the whole plant is more or less acrid or biting to the taste." 



REFERENCES. 

 17, 19, 73, 190, 204, 213. 



THYMELACE^. 



Mezereon {Daphne Mezereum L.) and Spurge Laurel {D. Laureola 

 L.). Both of these species are acrid and poisonous, and cases of the 

 death of horses due to the spurge laurel are recorded by Lander. In 

 general, however, animals will not eat the plants, and indeed, in one of the 

 cases mentioned by Lander the dried leaves were administered for 

 worms. Should they touch these plants most animals would probably 

 refuse them on account of their bitter taste. The berries are tempting 

 to children, and Pratt says " Death has resulted from eating but a few 

 of these berries (D. Mezereum) ; and Dr Christison relates a case' of 

 a child, in Edinburgh, who died from eating them, while another is 

 recorded by Linnaeus of a young lady to whom twelve of the berries 

 were given as a medicine in intermittent fever, and who soon died in 

 consequence of their corrosive poison. Four berries produced thirst, 

 sense of heat in the mouth and throat, and also fever, in a man who ate 

 them; and they are proved to be poisonous to dogs and foxes." Blyth 

 states that 30 grammes (1 oz.) of the powdered bark is a lethal dose for 

 a horse, but smaller doses of the fresh leaves may be deadly (Pammel). 



Toxic Principle. All parts of these plants are acrid and poisonous, 

 especially the bark and berries. They contain the bitter, astringent, 

 and poisonous glucoside Daphnin {^so^s^^id — ^^ ^is^ie^g according 

 to Van Rijn), an acrid resin (Mezerein), and a vesicating fatty oil. (Pott 

 remarks that Daphnin is believed to be harmless, but that Mezerein has 

 poisonous effects.) Drying does not destroy the poisonous property. 



Symptoms. The Daphnes are severely purgative, cause burning 

 in the mouth and throat, and in severe cases have narcotic effects and 

 give rise to convulsions. 



Lander gives the symptoms as intense colic, constipation, followed 

 by dysentery and copious evacuations of faeces streaked with mucus, 

 blood, and intestinal epithelium. Drowsiness between the spasms. 



L. 5 



