176 VETEEINAEY HYGIENE 



possessing deleterious properties. It can be distinguished 

 by the bluish-green colour of the leaves, and by the fact 

 that each of the small simple umbels which unite to form 

 the comjpound inflorescence has three narrow pointed bracts 

 projecting vertically downwards from it. These give the 

 inflorescence a very distinctive appearance. 



The deleterious properties of this plant are denied by 

 some, and it is said Linnaeus gave it to cows, sheep, and 

 horses, without apparent injury. 



The American Water Hemlock, Cicuta maculata, is 

 extremely poisonous, and is responsible for the bulk of 

 sheep and cattle poisoning in the United States.* Both 

 the leaves and rhizomes are virulent ; the latter smell of 

 parsnips with a slight addition of musk. A piece of the 

 Oregon Hemlock the size of a Walnut will kill a cow. The 

 poison is a toxine and not an alkaloid. 



The English species of this genus, Cicuta virosa, the 

 Cowbane (Fig. 42), is found growing in moist places, gener- 

 ally by the edges of ponds or ditches. It has a large fleshy 

 rhizome containing a yellow opalescent juice, and peculiar 

 in being hollowed out into several chambers in its interior. 

 The stem is furrowed and bears flowers and fruit of the 

 typical Umbelliferous character, the fruit being marked by 

 the teeth of the calyx projecting above it. The poisonous 

 properties resemble those of Hemlock. 



The genus CEnanthe has several poisonous species. 

 The most prominent of these are CE. crocata and (E. _2j/ieZ- 

 landriimi, both often called Water Dropwort. The former 

 (Fig. 43) is the more virulent, the poisonous properties re- 

 siding chiefly in its fleshy tuberous rhizomes which somewhat 

 resemble parsnips. The plant is often about four feet high, 

 and its leaves, though much divided like those of Hemlock, 

 are larger and the segments coarser. The acid sap of the 

 succulent part turns] yellow on exposure to air. CE. phel- 

 landrkim frequently grows in water, and its rhizomes are 

 then long and slender. The segments of the leaves are 



* ' Poisonous Plants,' by V. K. Chesnut, Year Book, Department of 

 Agriculture, U.S.A., 1900. 



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