306 Mr. R. Kidston on the Affinities of the 



this is veiy marked, causing it to have a truncated triangular 



outline. 



The general contour of the other segments is quadrate ; 



their sides are parallel ; but the constrictions of the spike at 



the nodal regions cause a rounding of their angles. 



The circumference of each segment has had about fourteen 

 longitudinal rows of sporangia- On the surface exhibited on 

 the fossil four rows are seen to occupy the greater portion of 

 each segment ; but on each side, one, or perhaps two, additional 

 longitudinal rows of sporangia are exhibited. These, on 

 account of the flattening of a once circular structure, appear 

 now merely as longitudinal lateral ridges. 



The sporangial ridges run continuously throughout the whole 

 length of the spike, and do not alternate at the nodes. 



On the upper segments of the spike these longitudinal 

 elevations bear little quadrate protuberances with rounded 

 angles and slightly notched sides (PL XII. fig. 10). Their 

 outline is ill defined. 



On the basal and older segment a few of the characteristic 

 stellate bodies are shown. These are not so clearly seen as 

 in Pothocites Grantoniij but are quite discernible (PL XII. 



fig. 17). 



They are of about the same size as the quadrate bodies 

 mentioned as occurring on the upper segments. 



From this similarity in size it would appear that the stellate 

 bodies are formed by the quadrate protuberances splitting in 

 lines running from their centre to the apices of their rounded 

 angles ; and the four segments so divided subsequently become 

 deflexed. 



From the facility with which one can trace the develop- 

 ment of the stellate bodies on this specimen, I am forced to the 

 conclusion that the so-called " four-cleft calyx " is merely the 

 deflected segments of sporangia which have shed their spores. 



The sporangia connecting elevated transverse ridges, to 

 which reference has been already made, are very well shown 

 on this example. 



The outer surface of the quadrate protuberances is roughened 

 by slightly elongated apiculi. 



The stem to which the fruit is attached shows three swollen 

 nodes and is faintly striated longitudinally. 



Its upper internode is very short, and measures only three 

 tenths of an inch in length and a little less than two tenths of 

 an inch in breadth. The internode immediately below it 

 measures fully half an inch in length; whilst the lowest is four 

 fifths of an inch long. The fourth internode is incomplete. 

 The stem increases slightly in breadth from above downwards. 





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