85 
THE JURASSIC FLORA OF YORKSHIRE. 
. SEW: ae MPAL HVS) 21. 
(Continued Pom: page 8). 
(PLATES V. and v1). 
The fossil reproduced in figure 3 is one of the specimens 
from the late Professor Williamson’s Collection, presented to 
the Cambridge Botany School by Mrs. Crawford Williamson. 
As seen in the photograph, the actual base of the specimen is 
not preserved, but the surface is covered by numerous linear 
bracts bent over towards the apex, and forming a protective 
Fic. 3. [Williamsonia gigas (Lind. & Hutt). From a specimen in the 
Wilhamson Collection, Botany School, Cambridge. Natural size. 
covering to the oval flower or inflorescence which was originally 
borne at the apex of a fertile branch. The centre, now repre- 
sented by a cavity, was no doubt occupied by a conical mass of 
tissue from which were given off slender seed-bearing appen- 
dages and interseminal scales. Between the broken ends of 
the bracts and the central space the fossil shows an obliquely 
inclined zone, characterised by numerous radiating lines, which 
may be regarded as the impressions of some of the appendages 
attached to the basal part of the conical axis of the flowering 
branch. Our knowledge of the structure of this type of Cyca- 
dean flower is still very incomplete, and additional specimens 
are urgently needed. 
ig1t Feb r. 
