534 Worsdell. — Observations on the Vascular 
part of the sporangium, but not extending as far as the 
nucellus ; these strands were in both cases quite unaccom- 
panied by tracheides, although a tracheide or two was 
observed on the edge of the tissue of the scale as if about to 
enter the sporangium. 
In radial section it is distinctly seen how the integument 
has become fused with the tissues of the seminiferous scale ; 
but on its inner side at the micropyle it is free for a very 
short distance. On its outer side the narrow strip of tissue 
pertaining to the scale appears to be continuous with the 
integument to the tip. 
The tracheides of all the bundles have spiral thickenings, 
those of the secondary elements being very close and dense ; 
the elements are extremely narrow and elongated. 
Branched sclerides, as in A. Cookii , R. Br., are abundant 
everywhere, except in the tissue surrounding the sporangium, 
which is devoid both of these and of tannin-sacs, but the latter 
occur in the outer narrow portion of the scale. 
In the free laminar portion of the seminiferous scale the 
bundles almost entirely lose their concentric structure, al- 
though some are curved towards their dorsal side. In 
some of these bundles a small quantity of centripetal 
xylem occurs, which here and there is fairly well developed 
(Fig. 8). 
Holding the theory of the axillary bud as the explanation 
of the structure of the appendage of the cone in Araucaria , 
I believe, with Celakovsky, that the ‘ ligule ’ represents the 
seminiferous scale which is itself the vegetatively-developed 
outer integument of a sporangium situated in the anterior 
position on an axillary bud. This outer integument has 
become almost completely fused with the subtending bract in 
Araucaria , completely so in Agathis. The seminiferous scale 
has thus in this section almost entirely lost its individuality. 
Is there any evidence in the structure of the vascular bundle- 
system for the original separation of the ventral scale or 
ligule as a distinct organ? In A. brasiliana , A. Rich., 
A. excelsa, R. Br., A. Cunninghami , Sw., and A. Cookii , R. Br., 
