1921] JEFFREY & TORREY—HERBACEOUS ANGIOSPERMS 29 
8. Absence of secondary growth extends from the leaf traces 
to the rest of the bundles situated in the stem, and a condition 
practically monocotyledonous results. 
HARVARD UNIVERSITY 
LITERATURE CITED 
1. CHRYSLER, M. A., The nodes of grasses. Bot. GAZ. 41:1-16. 1906. 
2. Eames, A. J., The herbaceous type in angiosperms. Ann. Botany 
25: 215-224. Iori. 
oAR, C.S., The a and phylogenetic position of the Betulaceae. 
Adar Jour. Bot. 3:415-534. 
4. JEFFREY, E. C., The pe of woody plants. University of Chicago 
Press. 1917. 
5. Sunnott, E. W., and Barry, I. W., The origin and dispersal of her- 
baceous angiosperms. Ann. Botany 28:547-600. 1914. 
6. , Anatomical evidence of reduction in certain Amentiferae. 
Bor. Gaz. 58: fete. 1914. 
7. WuIT. Epitn S., The anatomy a certain goldenrods. Bor. 
Gaz, $61795-260. 1018 
EXPLANATION OF PLATES I-VII 
PLATE I 
IG. 1.—Transverse section of lower region of aerial stem of Aster novae- 
angliae, slightly magnified to show presence of foliar rays on upper left hand. 
Fic. 2.—Transverse section of extreme upper slender portion of stem of 
Aster novae-angliae, slightly magnified to show alternation of leaf traces and 
leaf rays with ordinary stem bundles (approximately 8 of each). 
Fic. 3.—Part of fig. 2, more highly ma 
Fic. 4.—Part of fig. 2, more highly seideatiedt, 
Fic. 5.—Part of fig. 2, more highly magnified. 
Fic. 6.—Leaf trace and subtending and flanking storage tissue, from 
slender upper portion of stem of Aster novae-angliae. 
Fic. 7.—Leaf ray of Helianthus annuus in transverse section, slightly 
magnified . 
PLATE II 
Fic. 8.—Transverse section of foliar ray of Helianthus orgyalis, moderately 
magnified. ; 
Fic. 9.—Longitudinal section of foliar ray of H. tuberosus, somewhat 
can magnified to show mixed organization consisting of rays, fibers, and 
essels. 
Fic. 10.—Tangential section of leaf ray of H. hirsutus, showing it as yet 
incompletely aggregated from elements of ordinary wood and consequently 
consisting of an obviously mixed assemblage of wood rays, vessels, and fibers. 
