68 



PARSLEY OR CARROT FAMILY {Umhelliferae) 



POISON HEMLOCK {Conium maculatum L.) 

 Plate XXVI. 



Common Names: — This plant, known from early days as hemlock or 

 wild hemlock, has a number of other common names, a few of which are 

 snakeweed, spotted parsley, poison-root, wode-whistle. 



Description : — An erect, much-branched biennial with round, smooth, 

 hollow stems from two to six feet high, covered with purplish spots which 

 usually disappear on drying. The leaves are large, shining, decompound, 

 with finely-cut leaflets, which have a very foetid and characteristic mousy 

 odour when crushed. The leaves are much more delicate in outline than 

 those of the water hemlock (cf. illustrations), the ultimate segments 

 ending in a small, colourless, bristle-tip. The flowers are small, white, 

 in large loose umbels, with a circle of bracts or small leaves at the base of 

 the umbels. The fruit or ''seed" clusters, as they are popularly called, 

 are conspicuous in late summer and autumn. Each fruit is composed of 

 two parts, so close together as to resemble one round seed, somewhat 

 flattened on each side, with wavy ridges running from top to bottom. 

 Each part contains one seed, which is deeply grooved on the inner face. 

 The root is from eight to ten inches long and about one inch in diameter, 

 tapering, sometimes forked. It smells very much Hke the parsnip. The 

 plant is in bloom from June to August. 



Distribution: — Naturalized from Europe, the poison hemlock is 

 found in waste places, chiefly on dry ground from Nova Scotia to Ontario, 

 also in British Columbia. 



Poisonous Properties: — It is a question as to which part of the 

 plant is most poisonous, since authorities differ, but, as fatalities have 

 resulted from the consumption of even a very small portion of the leaves 

 or seeds or roots, it may well be said that the whole plant is deadly. It 

 seems that early in the summer the poisonous properties are most abundant 

 in the green leaves, and that later on the seeds are the most toxic, particu- 

 larly just before ripening. As the poisons are volatile the plant loses its 

 toxicity on drying, and consequently is not so dangerous to animals when 

 dried with the hay. The seeds, however, are most poisonous when fully 

 formed but still green in colour. When fully ripened their toxicity gradually 

 diminishes. 



The plant contains the very poisonous alkaloid coniine, a colourless 

 liquid which gives the plant the characteristic, disagreeable, mousy odour. 

 The poisonous coniceine and the alkaloid methyl-coniine are also present, 

 as well as other substances. Greenish states, ''Hemlock herb contains 

 coniine and conhydrine. These alkaloids are present in both stem and 



