282 Sinnott and Bartlett — Coniferous Woods. 



poorly marked. Wood parenchyma is scattered throughout 

 the year's growth but not abundantly. As seen in radial sec- 

 tion the tracheid walls display numerous large (rarely smaller) 

 bordered pits usually in one row, though in the wider cells 

 they are often in two rows and opposite. "Bars of Sanio " 

 are well developed between the pits. Small tangential pits 

 occur sparingly at the end of the year's growth. The walls of 

 the medullary rays are thin and devoid of pitting. In the 

 majority of cases there is but a single pit in each " crossing 

 field " between tracheid and ray cell, although in the larger 

 tracheicls there are commonly two and rarely even three. The 

 pit outline is generally large and elongated horizontally, some- 

 times big enough to cover almost the whole crossing field. The 

 pore is either of medium size, a vertically or obliquely elon- 

 gated opening, in which case the border of the- pit is necessa- 

 rily very wide ; or the pore may be so much enlarged as nearly 

 to equal the pit outline in dimensions, resulting in the reduc- 

 tion or even the disappearance of the border and the production 

 of a huge " eipore." This enlargement may perhaps be some- 

 times due to conditions of preservation or, as in many of the 

 living Podocarpineae, it may be quite normal. The ray pitting 

 may, therefore, be said to vary from " podocarpoid " to " eipo- 

 rig," in the sense of Gothan. The most striking characteristic 

 of the medullary rays, however, is the extreme height of many 

 of them. The majority, as seen in tangential section, are from 

 three to ten cells high, but scattered rather frequently among 

 these, especially in certain of the specimens, are others which 

 are very much taller, often running up to sixty and in one case 

 even apparently to ninety cells in height. These very high 

 rays are probably due to the linking up of shorter ones verti- 

 cally, for several cases were observed where the toj> of one 

 medium-sized ray was close to the bottom of another. As may 

 be seen in the figures both of the transverse and tangential sec- 

 tions, a large percentage of the rays are biseriate. 



Relationships. 



In the width of the tracheicls, the character of the lateral 

 ray pits and the height and frequently biseriate condition of the 

 rays, this fossil so much resembles Cupressinoxylon McGeei 

 Knowlton as to leave little doubt that the two are identical. 

 One charcoal fragment possessing slightly narrower tracheids 

 and smaller pitting displays certain resemblances to Knowl- 

 ton's Cujwessinoxylon Wardi, which was collected from near 

 our localities (Railroad cut near Montello, D. C.) and may per- 

 haps be identical with that species. It is so close to C. McGeei, 

 however (in which some of the tracheicls often show much 

 smaller pits than others), that it seems best at present to place 



