230 DESCRIPTION OF FOSSIL PALM-WOOD. 
same general characters of the fossilized parts of the carapace, but differs in the 
narrower proportions of the vertebral scutes, and the more open angle at which 
their two lateral borders meet : the vertebral angles of the costal scutes being 
correspondingly less acute. ‘The specimen consists of the seven anterior neural 
plates, and the corresponding seven pairs of costal plates. 
The neural plates correspond in form with those of the Chelone convera: the 
first is crossed at its middle part by the impression dividing the first from the 
second vertebral scute: the second neural plate is an oblong four-sided one, with 
both ends of equal breadth. The third neural plate resumes the hexagonal figure 
with the broadest end and two shortest sides at the fore part ; and is crossed in 
its lower half by the impression dividing the second from the third vertebral 
scute. The fifth neural plate is crossed by the next transverse impression nearer 
its lower border. The sixth and seventh scutes retain the same form and propor- 
tions as in the Chelone conveva, and have not their antero-lateral borders increased 
in length, as in the Chelone longiceps. ‘The declination of the ribs from the neural 
plates gives the same degree of convexity to the carapace as in the Chelone 
convexa, and the impressions of the scutes have the same depth and breadth. 
The only difference indicative of specific distinction lies in the form of the scutes : 
and the question is, whether, in the progress of growth which makes the longi- 
tudinal extent of two of the vertebral scutes nearly equal to three, so great a 
change could be effected in their shape as is shown in the specimen of Chelone 
conveea, in which it will be seen that the second vertebral scute, though more 
than one-third longer in Chel. declivis, is of the same breadth as that in the smaller 
specimen of the Chel. convewa, and that the fourth vertebral scute preserves the 
same length without diminishing in breadth as it does in the Chelone conveva. 
Notes on Fossil Palm- Stems, and Wood from the shore of Sussex. 
Amonesr the pebbles of the beach on the Sussex coast are occasionally disco- 
vered portions of fossil wood. 1am well-aware that from rolled specimens no 
satisfactory evidence can be produced as to the geological period when the 
various trees and plants were in existence ; yet as several of them indicate re- 
markable characters, which have not hitherto been noticed in this country, and 
are well observed by having thin slices placed under the microscope, I am 
anxious to add a short account of the more curious examples, and I have great 
