208 DESCRIPTIVE CATALOGUE 



theso are not due to the eating out of fungi or bacteria, and are 

 therefore not a true character. A number of the cells of the 

 ray are packed with dark granules, which may partly represent 

 resinous contents. Other cells have a very delicate granular 

 content centreing round what has every appearance of being 

 a nucleus. 



In several cases two rays come very close to each other, and 

 arc then connected by extremely short, irregularly shaped 

 tracheids. These can be seen in PI. XIX, tigs. '2 & 3, 

 and perhaps more clearly in the text-figure. Here they are so 

 short and specialised that they almost merge into ray-traeheids. 

 Their presence in this ancient fossil is interesting in Connection 

 with various published views on the origin of the ray-tracheids 

 (see Thompson, 1910, Holden, 191.'*, etc.). Once more th> 

 older fossils undermine rather than support the conclusions 

 drawn from the study of more recent fossils and living plants. 



AFFINITIKS. This fossil is doubtless a Tn.ro.i-i/lon closely allied 

 to the living Taxiis and Ton-ryu, though there appear to be 

 no other records of true Tajcoxyl on-wood at so early a date. 

 The spiral thickening of the tracheid-walls, while it is delicate 

 and has to be sought for with the high power, is clearly to he 

 seen in several places in the longitudinal sections. The bordered 

 pits in groups of three or four per tracheid-tield are also \<>i y 

 clearly to be seen in many of the medullary ray-cells; and both 

 these important features point conclusively to the Tnxii 

 when coupled with the lack of abietineau pitting in the end 

 and horizontal walls of the ray-cells. The arrangement of the 

 pi Is in tracheid- and ray-cells, and the spiral thickening of the 

 tracheids in the fossil, are very like those found in the living 

 Psem.lotsiuf't nuicrocai'ptt, but in this living spi-eies true abie- 

 tinean pitting of the end and horizontal walls is well developed. 



A Senouian Tu.coxylon was described by Hosius & von der 

 Marck (1SSO, p. 194) as T. lialtcrmanum^ but comparison with 

 our fossil is not possible, because the only critical feature figured 

 or described is a minute fragment showing spiral thickening of 

 the tracheid. walls. 



I know of no other Cretaceous woods with which one can 

 compare the new fossil. There are, however, many foliage 

 and even fruit impressions which have been attributed to Ttt t nis 

 and CtjtlmlotiL'ctis from various Cretaceous deposits. Their 



