104 DESCRIPTIVE CATALOGUE 



The narrow marginal tracheids found in our fossil, as in his, 

 are u in marked contrast to the other Cretaceous Pityoxyla,, 

 especially Pityoxylon statenense and P. scituatense of Jeffrey & 

 Chrysler, in which the marginal cells are not noticeably narrower 

 than the central cells of the ray " (Bailey, 1911, p. 317) ; but 

 in this feature they resemble Pityoxylon (called by Bailey 

 Pinus) scituatensiformis, though in other respects our much 

 older fossil is more highly advanced and more like the living 

 genus than is the Upper Cretaceous fossil. 



Turning to Tertiary fossils, though several species of Pityoccylon 

 have been described, none come very close to the new species. 



The genus Pityoxylon, Kraus, in a wide sense, comprises 

 several forms representing widely distinct modern genera 

 within the Abietincae. In many cases, the fossils do not show 

 sufficiently salient features to make possible any close com- 

 parison with living genera, but in the present instance the 

 fossil is not only well enough preserved, but has such cha- 

 racteristic features in its resin-canals, and in particular in 

 its ray-tracheids, that affinity with Pinus is securely established. 

 Among those species of living Pinus which I have personally 

 examined, P. monticola comes in many respects very near to the 

 fossil. It has large resinous parenchyma-cells in the rays, 

 each with large single pits in each tracheid-ficld. Above and 

 below the ray, and in narrow bands interspersed between the 

 parenchyma-cells, are narrow simple tracheids extremely like 

 those in the fossil (compare text fig. 23 with text-fig. 25). 

 Nevertheless, great as is the likeness to Pinus, I think the 

 fossil species is best described as Pityoxylon, especially as 

 the leaves or cones of this ancient form remain unknown. 



It thus appears likely that the new species had affinities with 

 the " soft pines " : as no dentate thickenings appear to be 

 developed on its otherwise well-preserved cell-walls, it seems 

 fair to conclude that they were normally absent. 



V. 1440. Type-specimen. A large wedge of secondary wood 

 (about 27 X 13 x 6 cm.), and some smaller pieces of it 

 from which the sections have been cut. The petrifac- 

 tion is clean of matrix, and shows the woody texture 

 in the longitudinal direction very clearly. Both in 

 the cut and the weathered transverse surfaces the very 



