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XIX. — Contributions towards a Knowledge of the Anatomy of the Lower 
Dicotyledons. II. The Anatomy of the Stem of the Berberidacese. By 
R. J. Harvey-Gibson, C.B.E., D.L., M.A., Professor of Botany, University 
of Liverpool; and Elsie Horsman, M.Sc. (With One Plate.) 
(MS. received November 22, 1918. Read January 20, 1919. Issued separately May 21, 1919.) 
Introductory. 
The present paper is the second of a series of investigations into the anatomy 
of the lower Dicotyledons (l), aiming at the accumulation of anatomical data 
which, it is hoped, may prove of service in elucidating the phylogeny of the 
complex of orders usually regarded as situated somewhere near the base of the 
Angiosperm phylum. The continuance of the War has again materially retarded 
these investigations, and has also rendered it almost impossible to obtain material 
from abroad that would, doubtless, have been available in peace time. We 
are greatly indebted for substantial assistance in this relation more especially 
to Sir David Prain, F.R.S., Director of the Royal Botanic Gardens, Kew, and to 
Sir Frederick Moore, F.R.S., Director of the Glasnevin Gardens, Dublin, and to 
them we tender our grateful thanks. 
According to Prantl (2), the order Berberidacese includes eight genera — 
Podophyllum, Jeffersonia, Diphylleia, Achlys, Nandina, Bpimedium, Leontice, and 
Berberis (including Mahonia). To these Lotsy (3) adds Hydrastis and Glaucidium, 
which Prantl places among the Ranunculacese. The Lardizabalaceae are included 
in the Berberidacese by Solereder (4), as also by Bentham and Hooker (5), 
while Berberidopsis, sometimes placed in Berberidacese, is included in Flacourtiacese 
by other authors. In the following pages seven of the eight genera of Berberi- 
dacese, as enumerated by Prantl, and representatives of four genera of the 
Lardizabalacese, viz. Lardizabala, Stauntonia, Akebia, and Decaisnea are discussed. 
For detailed treatment the common Barberry, Berberis vulgaris , L., has been 
selected, and its anatomy is compared with that of several other species of the 
genus. This has provided a basis on which to 'found a discussion of the other 
genera referred to, and has suggested certain general remarks on the relationships 
of the various types dealt with, both to each other and to members of other orders. 
The- Anatomy of the Stem of Berberis. 
Berberis vulgaris is a shrub with small simple leaves, with solitary spines 
formed by prolongation of the mid-ribs. Occasionally two additional spines 
TRANS. ROY SOC. ED1N., VOL. LII, PART III (NO. 19). 77 
are 
