Oct.. 1921] BECHTEL FLORAL ANATOMY OF URTICALES 
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of the column and labellum. Gerard (11) in 1879 presented the anatomical 
features of numerous genera of the Orchidaceae. Upon Darwin's discovery 
it was at once suggested that the Orchidaceae are probably in the same line 
of descent with the Amaryllidaceae. In all characters the genera agree 
anatomically except in the androecium, which varies in position and in the 
number of the stamens and staminodes. Van Tieghem (20) in 1868 
published the results of his extensive anatomical work on the flower, par- 
ticularly on the structure of the pistil. This study treats of the various 
positions of the ovary with reference to other parts of the flower. 
A search into flower anatomy should aid in revealing the following 
points: whether the same organs in different plants have taken on different 
functions; whether different organs perform the same function, or whether 
different forms of the same organ perform the same function (10); what is 
the condition of the vascular supply to aborted organs and to suppressed 
organs; whether any amplification in the floral organs has occurred; and 
what is the relative position of the floral organs, normal and abnormal. 
The order Urticales, a study of which forms the subject of this paper, 
has been nearly universally accepted as a natural primitive order, but has 
been placed otherwise, bodily or in part, by the following students of 
taxonomy: Weddell (21), Lindley (13), Bessey (3), and Hallier (12). 
Although these students have not looked upon this order as among the very 
primitive angiosperms, they do agree that it belongs among the lower 
archichlamydeous forms. This study of the group is based upon the 
anatomy of the flowers and has as its object the possible determination of 
the phylogenetic position of this group so far as evidence may be offered by 
this field of research in conjunction with other parallel evidence. 
Two treatments of the Urticales are in use to-day : that of Bentham and 
Hooker (2), which places all species in one family, the Urticaceae; and that 
of Engler (9), which divides the order into three families: Ulmaceae, 
Moraceae, and Urticaceae. For convenience in this paper the latter treat- 
ment is used. 
The following characters possessed by' this order of plants have caused 
them to be looked upon as primitive: flowers usually unisexual; floral 
envelopes composed of one whorl, which is generally spoken of as the calyx, 
and which is inconspicuous, bracteal, with parts similar and distinct or 
gamophyllous ; stamens isostemonous; ovary superior, one-celled and one- 
ovuled, the ovule commonly orthotropous. In spite of these fairly primitive 
characters these plants have nevertheless been looked upon as somewhat 
reduced forms, the very features considered primitive being viewed as 
simple by reduction. The evidence from which such a conclusion is drawn 
is: apetaly and one whorl of stamens (Bessey, 3) ; a pistil with a unilocular 
ovary but with two styles, an indication of two fused carpels. Syncarpy is 
not considered primitive nor is the solitary ovule (3, 9); these are, on the 
contrary, the result of reduction. In the present paper are shown cases in 
