UMBELLIFER^. 173 



properties ;' the alternation of the leaves,' and absence of stipules ; * 

 the isostemony of the androecium ; * the presence -of stylopods 

 or an epigynous disk ; the inflorescence in simple or compound 

 umbels.'' 



The other characters, eminently variable and establishing generic 

 and tribal distinctions and divisions into sub-orders are : the bracts 

 forming the involucres and involueels ; the form of the fruit and the 

 direction in which it is compressed, whether parallel or perpendicular 

 to the partition ; the presence of both primary and secondary ridges 

 or of one without the other, and developing or not into wings ; con- 

 striction or not at the commissure, narrow or wide in consequence ; 

 the number and position of vittse whether in the furrows or in the 

 substance of the ridges, irregular or interrupted or even disappearing 

 altogether ; the absence or presence of a carpophore which may be 

 single or double ; the form and size of the stylopods ; the configura- 

 tion of the ventral face of the seeds, flat, or traversed by a vertical 

 median furrow, broadly concave or involute at the margin. Of the 

 very diverse classifications based upon these differences and giving to 

 one or another a very variable relative importance, in still further 

 simplication, we have preferred that of Adanson, based upon the 

 form of the fruit," the characters of the flower and the envelopes of 

 the inflorescence, that is, involucres and involueels, and comprising 

 eight sections. By uniting two of these in one place, and three in 

 another, and by adding the Hydrocotylece and Eryngiem, we form six 

 series with the following distinctive characters : 



I. DAUCEiE.' — Fruit with primary and secondary ridges more or 



' Often also to the stems, &o. each side of the top of the sheath, a long snbu- 



2 Often opposite in Boiolesia, Spananthe, and late stipule. 



other Hydroeotyleae, several species of Arthro- * It disappears only in Plerandra. 



phpllum,Pa«ax, Hohenaekeria,\eTyTaiely\ei- 'Many scoaUed umbels are cymes. The 



ticillate. Some Gastonias have 3-5 folioles at latter are more frequent in the Araliece than 



the same level of the leaf-rachis. in other Umbelliferce. In one and the same 



3 Many^ra&cehave a dilatation of thepetiole, genus as Bydroootyle (see p. 141), umbels or 

 sometimes -with an aixillant scale, superposed to cymes may be observed according to the spe- 

 the furrow of the petiole. Bowlesia, MuUntim, cies. 



Azorella, Hydrocotyle, and several other plants ^ At this time considered as seeds. 



of the same series have scarious or squamiform ' Baucineoe Koch, Umbell. 76. — Endl. Gen. 784, 



stipules (P). In Aralia papyri/era, there is on trib. 12.— Zaserpidece B. H. Gen. 929, trib. 9. 



