262 VETEEINAEY TOXICOLOGY 



urinate are frequent and painful. The animal lies down, 

 the bladder becoming more distended, and dies in coma, or 

 in a violent effort at relief. 



The treatment is difficult save in the early stages. Epsom 

 salt and three-hourly doses of 10 grains of extract of bella- 

 donna have been recommended (Hutcheon). In the horse 

 the catheter may be used, and for the ox amputation of the 

 penis is a possible measure. Turpentine or any diuretic 

 agent is to be avoided. 



Mereurialis. 



Both M. perennis and M. annua are poisonous, and the 

 former is here described as typical. 



Botanical Characters. — M. perennis (Fig. 39), or dog's 

 mercury. Eootstock slender and creeping. Stems erect, 

 simple, 6 or 8 inches, or rarely nearly 1 foot high. Leaves 

 rather crowded in the upper half, oblong or ovate-lanceolate, 

 2 to 4 or 5 inches long, usually pointed, crenate or serrated, 

 and rough or with short hairs. Flowers dioecious, on slender 

 axillary peduncles, often nearly as long as the leaves ; the 

 males in little clusters, the females singly or two together. 

 Ovaries larger than the perianth, with rather long, spread- 

 ing styles. Capsules more or less covered with warts or 

 soft prickles. 



The plant is common in England and Scotland ; less so 

 in Ireland. 



Toxic Ppinciple. — Mereurialis has been found to contain 

 a volatile basic oil having narcotic properties, which has 

 been called mercurialine, and to which, in part at any rate, 

 the toxicity of the plant is due. 



Symptoms. — Mereurialis acts on the alimentary and 

 urinary systems. In a case observed by C. Blackhurst* of 

 the poisoning of cows, there was excessive bloody purgation, 

 cessation of lactation, temperature 105° F., pulse 90, and 

 increased respiration. The disease was protracted over 

 several weeks, the animals being comatose after the first 



* Vet. Jl., 1896, p. 431. 



