VOL. Lll.] PHILOSOPHICAL TRANSACTIONS. 531 



in the same places, and often mixed with it, so much resembling it in appearance, 

 as not, without some attention, to be distinguished from it ; which however 

 greatly differs from it in sensible qualities. Great care therefore ought to be 

 taken, that the one of these should be selected from the other. The plant so 

 much resembling hemlock, is the Cicutaria vulgaris of the botanists, which in 

 some parts of England is called cow-weed, in others wild cicely. Its greatest 

 resemblance to hemlock is in the spring, before the stalks of the leaves of the 

 hemlock are interspersed with purple spots ; and therefore at that season more 

 easily mistaken for it ; though even then the leaves of the hemlock smell much 

 stronger, are more minutely divided, and are of a deeper green colour, than those 

 of the cow-weed. Afterwards indeed they are more easily distinguished, as the 

 Cicutaria flowers at the end of April and beginning of May, and the Cicuta not 

 till June, when the other is past ; to say nothing of the flowering stalk of the 

 cow-weed being furrowed, and somewhat downy ; and that of the hemlock, 

 smooth, even, and always spotted. These plants differ likewise very essentially 

 in their seeds, which in the cow-weed are long, smooth, and black, when ripe ; 

 whereas those of the hemlock are small, channelled, and swelling towards the 

 middle. 



Besides the cow-weed, there is another plant in appearance very like the hem- 

 lock, though evidently differing from it in other respects ; and it seems quantities 

 of this have been collected, and sold in London for the hemlock. This is more 

 likely to be taken for the hemlock in summer or autumn, as it is an annual plant, 

 and is produced and flowers late in the season. The plant here meant is the 

 Cicuta minor of Parkinson, or Cicutaria tenuifolia of Ray. This however is 

 easily distinguished from hemlock, by its leaves being of the colour and shape of 

 parsley, its flowering stalks having no purple or other spots, and not having the 

 strong smell peculiar to hemlock. 



To the two plants before-mentioned, may be added a third, which very fre- 

 quently, more especially about London, grows along, and is mixed, with the 

 hemlock. This plant is called, by the late excellent Mr. Ray, Small hemlock- 

 chervil with rough seeds ; and is denominated by Caspar Bauhin, in his Pinax, 

 Myrrhis sylvestris seminibus asperis. This, like the cow-weed before-mentioned, 

 can only be mistaken for hemlock in the spring. It may be distinguished then 

 from it, by the leaves of the myrrhis being more finely cut, of a paler green cc- 

 lour, and, though they have somewhat of the hemlock smell, are far less strong, 

 and have no spots. This plant flowers in April, and the seeds are ripe before the 

 hemlock begins to flower ; and these seeds are cylindrical, rough, and terminate 

 in an oblong point. 



The leaves of hemlock are more fit for medical purposes, as being in their 

 greatest perfection, when collected in dry weather, from the middle of May to 



3 Y 2 



