UMBELLIFEBJE. 143 



or peltate at the base, which is more or less prolonged below the 

 point of insertion. The petals are inflexed and adnate at the summit, 

 forming a salient ridge which divides into two lobes. They are 

 shrubby or herbaceous plants, often covered with stellate hairs, with 

 simple, dentate, lobed or ternisect leaves. The flowers are in irre- 

 gularly compound umbels, with bracts sometimes wide and petaloid, 

 more rarely reduced to a few or even a single flower. In Siehera, the 

 sepals are nil or narrow, subulate ; the petals, concave, imbricate, 

 equal or nearly so ; the fruit, more or less constricted at the commis- 

 sure, has obtuse but generally distinct primary ridges but no or very 

 fine secondary, covered more or less externally with rugosities ; the 

 styles are often elongate and curved ; the carpophore is simple. They 

 are ericoid shrubs or perennial herbs, with alternate entire rarely 

 squamiform leaves ; the lower sometimes dissected. The flowers are 

 in simple or more generally compound umbels with an involucre of 

 small bracts. 



Azorella (fig. 166) is with us the type of a third group in which the 

 mericarps of the fruit are very constricted at the commissure, and 

 are attached to each other only by a central 

 linear edge corresponding to an undivided Azweiia trifoUata. 



carpophore. The form of the mericarps 

 varies in the true AzoreUas. In some they 

 are as wide as thick, in others laterally com- 

 pressed, in others dorsally. They bear each 

 five primary ridges, nearly equal, but slightly 

 prominent or even scarcely visible. One is 

 middle dorsal, the others vary in position 

 according to the form of the mericarps; 

 thus when the latter are dorsally compressed, 

 the margin being more or less thick and ^^^- ^^^- ^^^* (t)- 



smooth, there is one ridge without and one 



within this margin. The latter may be carried back more or less on 

 the face as in Spananthe, an American species with alternate or 

 opposite leaves, which we make only a section of Azorella. The 

 other sections are also founded on the habit and inflorescence. The 

 stems are most frequently csespitose. In Microsciadium and Pozoa, 

 the leaves are radical ; and the flowers form many-flowered or irre- 

 gularly branched umbels. In Fozoa the umbels are pedunculate, 

 simple, and the involucre is formed of bracts connate for a very 



