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Genus Pothocites, Pater son. 307 



One of the most interesting points shown on this specimen is 

 the verticils of leaves which are given off from the nodal 

 regions of both spike and stem. This is shown more or less 

 distinctly at all the nodes of stem and spike except at the 

 lowest node of the stem, where a verticil of tubercles marks 

 the site of the leaves which have fallen off. 



The remains of the largest leaf measure half an incli ; but 

 more important is their dichotomous structure as exhibited by 

 the leaves at the fourth, fifth, and sixth nodes of the fruit, 

 counting from the apex. 



This specimen was presented by Mr. Stock to Mr. John 

 Young, Curator of the Hunterian Museum, Glasgow Uni- 

 versity. My thanks are due to botli of these gentlemen for 

 allowing me to examine and describe this beautiful specimen. 



I am also indebted to Prof. A. Geikie, Director-General of 

 the Geological Survey of Great Britain, for kindly allowing 

 me the use of the specimens in the Geological Survey collec- 

 tion while preparing these notes. 



From the examination of these five specimens of Pothocites 

 it is shown that the plant possessed a segmented fructifying 

 spike or cone. In the only perfect specimen the fruit con- 

 sists of eight segments. The segments are formed by a 

 constriction which corresponds in position to the nodes of the 

 axis. On the circumference of each internodal portion of the 

 fruit there have been from ten to fourteen longitudinal eleva- 

 tions which bore sporangia ; these in the young state appear 

 externally as quadrate bodies, having their angles rounded 

 and a shallow notch on each side. The sporangia open in a 

 definite manner, by a cleft passing from the apices of the 

 angled corners towards their centre ; and by the margins of the 

 split sporangia becoming deflexed the so-called calyx-seg- 

 ments are formed. 



The spike is also attached to a stem composed of nodes and 

 internodes, which branched in a more or less equal dichoto- 

 mous manner, and bore, at the extremities of the dichotomous 



branches, cones or spikes. 



The stem also shows traces of longitudinal furrows. 



Verticillate dichotomously formed leaves are given off from 

 the nodes of both spike and stem. 



From such important structural evidence it appears no 

 longer possible to regard Pothocites as a Monocotyledon, and 

 I am inevitably led to the conclusion that Pothocites is not the 

 inflorescence of an Aroid, but the fructification of a Calami- 



taceous plant. 



But from the material before us we can, I think, place the 

 genus Pothocites in a much more defined systematic position 



