220 TII1C INFLORESCENCE. 



rescence, which we may observe in Drosera, Sedum, and Hounds- 

 tongue, imitate the raceme so nearly, that they have commonly been 

 considered as of that kind. They are distinguishable, however, by 

 the position of the flowers opposite the leaf or bract, or at least out 

 of its axil; while in the raceme, and in every modification of cen- 

 tripetal inflorescence, the flowers necessarily spring from the axils. 

 But if the bracts disappear, as they commonly do in the Forget-me- 

 not, &c, the true nature of the inflorescence is not readily made out. 

 The undeveloped summit is usually circulate, or coiled in a spiral 

 manner (Fig. 219), gradually unrolling as the flowers grow and 

 expand, and becoming straight in fruit On account of this coiled 

 arrangement, such cymes or false racemes are said to be helicoid, 

 or scorpio id. 



408. The cyme, raceme, head, &c, as well as the one-flowered 

 peduncle, may arise, either at the extremity of the stem or leafy 

 branch {terminal), or in the axil of the leaves (axillary). The case 

 of a peduncle opposite a leaf, as in the Poke, the Grape-vine, &c, is 

 just that illustrated in Fig. 333, except that in these cases the peduncles 

 bear a cluster of flowers instead of a single one. The tendrils of 

 the Vine (Fig. 161) occupy the same position, and are of the same 

 nature. In a growing Grape-vine, it is evident that the uppermost 

 tendril really terminates the stem ; and that the latter is continued 

 by the growth of the axillary bud, situated between the petiole and 

 the peduncle ; the branch thus formed, assuming the direction of the 

 main stem, and appearing to be its prolongation, throws the peduncle 

 or tendril to the side opposite the leaf. 



409. The extra-axillary peduncles of most species of Solanum, &c. 

 are terminal peduncles, which have become lateral by the evolution 

 of an axillary branch, with which the peduncle or the petiole is 

 united for some distance. Such peduncles sometimes come from 

 extra-axillary accessory buds (169). 



410. In the Linden (Fig. 742) the peduncle appears to spring 

 from the middle of a peculiar foliaceous bract. But this is rather 

 a bractlet, inserted on the middle of the peduncle, and decurrent 

 down to its base. 



411. A peduncle which arises from the stem at or beneath the 

 surface of the ground, as in Bloodroot, the Primrose, the so-called 

 stemless Violets, &c, is called a radical peduncle, or a Scapk. 



412. A combination of the two classes of inflorescence is not un- 

 usual, the general axis developing in one Avay, but the separate 



