10 



farinaceous and useful for food. In some cases the rootss are 

 fasciculate-tuberous, as in Ei/lophus^ Ticdemannia^ some species of 

 Caruin^ etc. Very few species are fibrous-rooted. 



Stem. While some Kamschatkan species attain a gigantic 

 size, and certain S. African forms become shrubs and even small 

 trees, our North American species are at most but coarse herbs. 

 The stems are grooved, more or less swollen at the joints, pithy 

 or hollow, and so uniform in cliaracter that none of these features 

 are useful in classification. 



Leaf. The leaves are alternate, with very characteristic 

 petioles, which are dilated (sometimes very much so) and more or 

 less sheathing at base. xA.s a rule, they arc compound, sometimes 

 simply lobed, very rarely entire. 



Inflorescence. — The general plan of inflorescence is a regu- 

 larly compounded umbel, but in certain genera (as in Hydrocotyle) 

 the umbels are simple; while in others they are reduced to 

 heads (as in Eryngiuni). In some genera the umbels are very 

 irregularly compounded, so that it would be almost impossible to 

 draw any satisfactory line between forms with simple and those 

 with compound umbels, although this character has been rather 

 extensively used in generic grouping. Even when this indistinct 

 line has been drawn the genera are thrown into most unnatural 

 relationships. Proliferous umbels are not at all uncommon, and in 

 some forms (as in Hydrocotyle^ prolification is a constant charac- 

 ter. The involucre (composed of bracts) and the involucel (com- 

 posed of bract/ets) furnish very important characters in classifica- 

 tion. The bracts and bractlets may be wanting, or from minute 

 to very conspicuous, green or scarious, distinct or more or less 

 united. 



The flower. — The small ejoigynous flowers, with five sepals 

 (often obsolete), petals and stamens, and bicarpellary pistil, are so 

 un-form in character that they cannot be considered of much value 

 in classification, unless we except such suboidinate characters as 

 the presence or absence of calyx-teeth, and the color of petals. 



Sepals. The calyx is blended with the inferior ovary and 



2 We use "roots" liere in the ordinary systematic way. Morpholo{jic;illy these "tuberous 

 roots" are mostly subterranean stems. 



