of Fossil Cone from the Calciferous Sandstone. 421 



the peduncle above described, except for the absence of any secondary 

 tissues. The wood has twelve prominent angles, at which the spiral 

 tracheae are situated, so its development was, no doubt, centripetal. 

 The inner tracheae have pitted walls, and are intermixed with scat- 

 tered parenchymatous cells, imperfectly preserved. The phloem has 

 entirely perished. 



The most interesting anatomical feature is the course of the leaf- 

 trace bundles, which can be followed with the greatest exactness on 

 comparing sections in the three directions. 



A single vascular bundle starts from each angle of the stele for 

 each sporophyll, and passes obliquely upwards. When less than 

 half way through the cortex, the trace divides into three bundles, 

 one median and two lateral. The lateral strands are not always both 

 given off exactly at the same point. A little farther out, the median 

 bundle divides into two, which in this case lie in the same radial 

 plane, so that one is anterior, and the other posterior. The median 

 posterior bundle is the larger, and before leaving the cortex this, in 

 its turn, divides into three. There are now six branches of the 

 original leaf-trace, three anterior, and three posterior, which respec- 

 tively supply the lower and upper lobes of the sporophyll. The three 

 segments of the lower lobe are supplied by the two lateral bundles 

 first given off, and by the anterior median bundle, while the upper 

 segments receive the posterior median bundle and its two lateral 

 branches. In the base of the sporophyll, all six bundles can be 

 clearly seen, in tangential sections of the cone, three above and three 

 below. As the segments become free, one bundle passes into each, 

 and runs right through the pedicel to the lamina. In the fertile 

 lamina the bundle subdivides, a branch diverging to the point of 

 insertion of each sporangium. 



One of the longitudinal sections passes through the base of the 

 cone, so as to show part of the peduncle in connection with it. In 

 this peduncle secondary wood is present, just as in the separate 

 specimen belonging to the Williamson collection. Higher up in 

 the axis of the cone, where the sporophylls begin to appear, the 

 secondary wood dies out. This evidence materially confirms the 

 conclusion that the Williamson peduncle really belongs to our 

 strobilus. 



Diagnosis. 



It is evidently necessary to establish a new genus for the reception 

 of this fossil; the generic name which I propose is Cheircstrobus, 

 intended to suggest the palmate division of the sporophyll-lobes 

 (x ei pi hand). The species maybe appropriately named Pettycurensis, 

 from the locality where the important deposit occurs, which has 

 yielded this strobilus and so many other valuable specimens of 



