2 
Plowman . — The Comparative Anatomy and 
Introduction. 
S INCE the publication of De Bary’s (12) great work on Comparative 
Anatomy, and Van Tieghem’s (57) subsequent ‘ stelar theories/ there 
has accumulated a considerable body of literature devoted to this phase 
of botanical study. The work of De Bary marked the culmination of that 
earlier mode of treatment which considered the axis of vascular plants to 
be made up of more or less numerous, wholly independent fibro-vascular 
bundles, embedded in a common matrix of fundamental tissue. Van 
Tieghem (57) later introduced the idea of a fundamental stelar unity of the 
fibro-vascular system, and showed that this unity held essentially true of 
all the Vasculares. The elaboration of this view lent new interest and 
broader possibilities to the anatomical study of plants ; and while many of 
the details and assumptions of Van Tieghem’s theory have been disproved 
or modified by the later investigations of Gwynne- Vaughan (20), Jeffrey (27), 
Boodle (4), Faull (18), Worsdell (61), Schoute (45), Chrysler (9), and others 
(5, 17, 21), yet the important fact still remains that in the fibro-vascular 
system of higher plants we find an essential unity of plan which is fairly 
comparable to that found in the skeletal system of vertebrate animals, and 
which is apparently of hardly less importance from the phylogenetic point 
of view. 
In the hope of gaining some new light upon the vexed question of the 
relationships of the Monocotyledons, the writer has undertaken the present 
study of the Cyperaceae, a group which is especially interesting on account 
of its apparently somewhat isolated position and its clearly-marked 
characters. 
Upon making a general survey of the problem before us, the following 
questions, among others, present themselves for careful consideration, if 
not, indeed, for solution : — 
i. Anatomically considered, do the Cyperaceae constitute a clearly- 
defined group ? 
2 . What subdivisions of the Cyperaceae may be made upon the basis 
of anatomical characters ? 
3 . Of what importance are oecological factors in determining the 
anatomical features of the group ? 
4 . What is the nature, origin, distribution, and significance of the 
amphivasal bundles found in this group ? 
5 . What is the course of the fibro-vascular bundles through the stem ? 
6 . Of what importance are leaves as factors in stelar development? 
7 . What structural characters of the Cyperaceae are ancestral, and 
what are more recently acquired ? 
8 . What are the probable phylogenetic inter-relationships of the 
Cyperaceae ? 
