280 SYSTEMATIC BOTANY. 



(Enanthe, Lam. 

 vEthusa, //. 

 Angelica, JFIoffm. 

 Ferula, L. 

 Heracleum, L. 



Series 3. DIPLOZYGTJE. Umbels 

 compound ; fruit, with both primary 

 and secondary ridges well marked. 



Coriandrum, L. 



Daucus, L. 



Thapsia, L. 

 Affinities, &c. The floral conformation may be thus expressed : | S o 



P 5 A 5 G 2. The arrangement of the genera above given is that of 

 Beutham and Hooker, who greatly reduce the number of genera cited by 

 other authors. By De Candolle the Umbellifers were grouped under three 

 Suborders : 1. Orthospermece ; perisperm flat on the inner face : 2. Campy - 

 lospermeee ; perisperm involute, with a vertical groove on the inner face : 

 3. Ccdospermece : perisperm inflexed above and below. The plants of this 

 very extensive and important Order are in general readily recognizable 

 by their inflorescence and fistular stems ; but these characters are not 

 always present, even in the indigenous forms ; and it is instructive in this 

 respect to examine the genera Sanicula and Hydrocotyle, where the umbels 

 are little developed, and Erynffium, where the flowers are sessile and the 

 involucral bracts so much developed as to give the umbels the appearance 

 of the capitula of Composites. These deviations from the ordinary habit 

 are still more striking in some of the exotic genera ; for HorxfieldtOj a 

 Javan form, has capitulate heads arranged in panicles ; and JBolax, an 

 Antarctic genus, grows in a tufted manner, with imbricated leaves and 

 nearly sessile umbels, so as to assume the outward appearance of some of 

 the alpine species of Androsace. In some of the genera the leaves are 

 entire, or the stalk of the leaf expanded into a blade-like form (Bupkurum, 

 Eryngium}. The essential character of the order lies in the fruit, by 

 which they are known from all other plants. The form of the fruit, the 

 structure and arrangement of the ridges and vittse upon the pericarp, 

 together with the form of the perisperm of the seed, and the characters 

 presented by the inflorescence, furnish the characters by which the Order 

 is subdivided ; the latter character, although formerly regarded as primary, 

 is now found to be too inconstant for that purpose. 



The relations of the Umbelliferee are closest with the other epigynous 

 Calyciflorse with definite stamens, especially Araliaceaa (from which their 

 fruit differs), the Rubiaceaa (which have sympetalous corollas and op- 

 posite leaves and interpetiolar stipules), and the Cornaceae (where the 

 leaves are partly opposite, the flowers tetramerous, and the fruit succulent). 

 In habit, as well as in dicarpellary structure, some of the Umbellifene 

 approach the Saxifragacese. The resemblances to GeraniaceaB seem 

 rather superficial : the carpophore is of very distinct character. 



Distribution. Abundant in the northern and central parts of Europe, 

 Asia, and America ; common upon the mountains of warmer regions, and 

 again met with in the Southern hemisphere, but chiefly as dwarf and 

 aberrant forms. 



Qualities and Uses. Several distinct classes of active secretions occur 

 in the plants of this Order, which in some are extremely powerful, and in 

 others slightly developed. The most important consist of aero-narcotic 

 poisonous substances in solution in the watery juices ; the second are 

 gum-resinous substances, and becoming milky when exposed to the air ; 



