Some Points in the Anatomy of the Leaf of 
Welwitschia mirabilis. 
BY 
H. TAKEDA. 
With Plate XXIX and five Figures in the Text. 
S INCE the publication of Hooker’s elaborate monograph (8), internal 
features of this singular plant have already been investigated by 
various botanists, such as de Bary (4), Bertrand (1), Strasburger (17, 18), 
and Bower (2, 3). Quite recently Miss Sykes (now Mrs. Thoday) has made 
contributions to our previous knowledge in two papers (19, 20), in which 
she refers to the publications of the previous workers. It seems to me, 
however, that there are still some interesting anatomical features left un- 
described, and also certain points requiring a thorough examination. 
The material of the adult leaf used for my study was dried. It was 
boiled in water for a short time and then soaked in spirit, and it shows the 
structure wonderfully well preserved. The whole leaf is 6o cm. in length 
and deeply cut into strips about 2 cm. in breadth. These strips are inserted 
on a stem io cm. in height, 17 cm. in the longer diameter, with much- 
branched roots. The cotyledon and young leaf of seedlings which were 
raised by Mr. Hales of Chelsea Physic Garden were also examined for 
comparison. One of the seedlings was about three weeks old and bore two 
cotyledons nearly 3 cm. in length, and 5J mm. in breadth. In this stage 
the leaves had not yet developed, but showed themselves as small projections 
at the apex of the hypocotyl between the connate bases of the cotyledons. 
The other seedling was about seven months old, and had developed 
young leaves about 6 cm. long. 
Sections were cut by hand or microtome in three directions : 
transverse, horizontal (parallel to the surface of the leaf), and longitudinal 
(radial to the vascular bundle). Certain elements of tissue were macerated 
out by means of Schultze’s macerating fluid. Various kinds of reagents 
and simple as well as combination stains were used. Some sections were 
mounted for permanent preparations in Canada balsam, or in glycerine- 
jelly either coloured or uncoloured. 
The Nervation. The nervation of the leaf is a simple sort of ‘ nervatio 
[Annals of Botany, Vol. XXVII. No. CVI. April, 1913. 
