41 8 Scott. — On Pedtmcle of Cycadaceae. 
The main results attained may be briefly summed up 
thus : — 
1. The peduncles of certain Cycads ( Stangeria paradoxa , 
J and $ ; Bowenia spectabilis , $ and $ ; Zamia Loddigesii, ? ; 
Ceratozamia mexicana and latifolia , ) have mesarch vascular 
bundles, comparable in structure to those of the leaves. 
This is, in my opinion, a primitive character, indicating 
affinity with the fossil Lyginodendreae and Poroxyleae. 
2. Some of the primary cortical bundles of the peduncle 
of Stangeria show concentric structure. Possibly this also 
may be a relic of ancestral organization. 
In conclusion I desire to express my thanks to Mr. W. C. 
Worsdell, to whose skilful aid in the investigation I am 
greatly indebted. The illustrations are also from his hand. 
EXPLANATION OF FIGURES IN PLATES 
XX AND XXI. 
Illustrating Dr. Scott’s paper on the Peduncle of Cycadaceae. 
The following abbreviations are used throughout the figures :—px. protoxylem ; 
x x . centripetal xylem ; x 2 . centrifugal xylem ; ph. phloem ; cb. cambium. 
PLATE XX. 
Fig. i. Stangeria paradoxa. Diagrammatic transverse section of the peduncle 
of a male cone, taken about half way up, showing the arrangement of the vascular 
bundles, and the distribution of the centripetal wood, indicated by dots ; c . s. 
cortical strands. The numerals indicate corresponding bundles in this section and 
the next, x about 12. 
Fig. 2. Stangeria paradoxa. Similar section from the lower part of the same 
peduncle, at the level where the centripetal wood first appears. Note the irregular 
orientation of the bundles in this region, c. s. cortical strands, one of which is 
concentric, x about 12. 
Fig. 3. Stangeria paradoxa. Transverse section of a vascular bundle from the 
upper part of a male peduncle. The centripetal xylem is well developed, and 
abuts on the compressed protoxylem. x 85. 
