POISONOUS PLANTS 259 



email purple-scented flowers appear in February before the 

 leaves are fully out. The berry is red. 



The spurge-laurel (Fig. 38) attains about 4 feet, and has 

 clusters of evergreen lanceolate leaves crowded at the ends 

 of the branches. The flowers are greenish-white and 

 scentless, and the berries bluish-black. 



Active Principle. — The daphnes contain an acrid sub- 

 stance, mezerinic acid, in all parts, particularly the bark and 

 berries. It is not destroyed by drying. Very little is known 

 as to the chemistry and properties of mezerinic acid. The 

 physiological effect is that of a powerful drastic, also ex- 

 hibiting marked nervous effects. 



The plants are very poisonous. Twelve berries of meze- 

 reon have been stated to kill the human subject, and about 

 1 ounce of the spurge-laurel is stated to prove fatal to the 

 horse. 



A case of poisoning of a horse by spurge-laurel (locally 

 known as wood-laurel) was investigated by the author (1911) 

 for H. D. Sparrow, of Eochford, Essex. From Sparrow's 

 information it appears that the leaves are frequently dried, 

 rubbed up in the hands, and given to horses for worms. 

 In a case observed by him such administration preceded 

 attacks of gripes. Several mysterious cases of colic en- 

 countered in the district would appear to have been caused 

 by this practice. 



Symptoms. — Daphne poisoning is marked by intense 

 colic. As an immediate effect Sparrow noted constipation, 

 lasting in one instance forty-eight hours, in spite of aloes, 

 oil, and 1 grain eserine and 2 grains pilocarpine intra- 

 venously. There follow dysentery and copious evacuations 

 of faeces streaked with mucus, blood, and intestinal epi- 

 thelium. Between the spasms the animal is drowsy. 



A similar case came under observation (1912) through 

 C. F. Parsons, of Cheltenham, in the case of a seven-year- 

 old cart-horse. The horse ate the shrub whilst waiting to 

 be unloaded, and refused the evening meal of the same day. 

 On the next day there was abdominal pain, staggering gait, 

 anxious countenance, laboured breathing, pulse 80, tem- 



