24 POISONOUS PLANTS 



and Hemlock (Fig. 22), several in the Poppy-head 



(Fig. 13). 



The number of parts in the whorls may vary 

 from two to six, being rarely more unless the 

 flower be " double." Fours and fives prevail in 

 Dicotyledons and threes in Monocotyledons ; 

 these being the two great classes which contain 

 all flowering plants. 



Lastly, any whorl may be regular or irregular ; 

 i. e. if the parts be all exactly alike, or with some 

 of them unlike. Thus in a Buttercup (Fig. i) and 

 Primrose every whorl is regular ; but in the Lark- 

 spur and Aconite (Fig. 12) the sepals are irregular, 

 and in all members of the Foxglove family as well 

 as that of the Labiates — not referred to in this 

 book as they contain no poisonous plant — the 

 corolla is irregular, as seen in the common Dead- 

 nettle and Sage. 



CLASSIFICATION. 



Before discussing individual poisonous plants, 

 we must consider on what principles they are 

 arranged ; to do this we can follow the lines of 

 historical botany ; for, at first, as a general rule, 

 every plant was known by a single name ; but it 

 was early observed that in many cases there were 

 obviously plants so much alike that they all had 

 to be called by the same name ; but, at the same 



