338 TEXTBOOK OF BOTANY 



genus Cicuta, are closely related to conium and are likewise 

 extremely poisonous. Several human deaths are caused 

 each year by the eating of the parts, especially the roots, of 

 the water hemlock and poison hemlock. The similarity of 

 these plants to the cultivated parsnip seems to have been 

 the foundation of the widespread though incorrect notion 

 that the parsnip becomes poisonous if allowed to grow wild. 

 Sometimes the seeds of conium have been mistaken for those 

 of anise, and the leaves for those of parsley, with fatal results. 



Com cockle, a rather common weed in grain fields, is poi- 

 sonous. The chief danger from it seems to arise from the 

 mixing of the seeds with wheat or other grains. Flour made 

 from wheat containing cockle seeds has been known to pro- 

 duce serious, sometimes fatal, effects. 



The juices of various spurges are poisonous. Two culti- 

 vated species which sometimes cause trouble are caper spurge 

 and " snow-on-the-mountain." The seeds of' the former, if 

 eaten in too large numbers, cause illness and even death; 

 and the poison of snow-on-the-mountain is carried by honey 

 made from the nectar of the flowers. Honey obtained from 

 the broad-leaf laurel also is said sometimes to be poisonous ; 

 and children are reported to have been poisoned by eating 

 the young shoots of this plant which they mistook for winter- 

 green. The narrow-leaf laurel and the great laurel are like- 

 wise poisonous. 



There has been much discussion as to the poisonous nature 

 of the black nightshade. The ripe fruits are said to have 

 been eaten in considerable quantities without bad effects ; 

 on the other hand, cases have been reported of the poisoning 

 of domestic animals by the eating of the leaves, and experi- 

 ments seem to show that the berries are sometimes poisonous. 

 The berries and leaves of the bittersweet, which, like the 

 nightshade, belongs to the same genus as the potato, have 

 been found to be somewhat poisonous. 



There are some plants which are regularly used for food in 



