123 
Abietineae (?) from the Cretaceous of New Zealand. 
(see Bentham, 1873, and Cheeseman, 1906)* In New Zealand, indeed, the only 
endemic Conifers are the genera Agathis, Librocedrus (a misleading name — 
the plant has nothing whatever to do with Cedrus ), P odocarpus , Dacrydium , 
and Phyllocladtts. Not one of these forms has structure at all like the 
fossil, so far as present discoveries go. The ray structure of the Podo- 
carpaceae, as is well known, is typically very different from that of the 
Abietineae. 
A word of warning must be uttered : this new fossil, with its mixture of 
Araucarian and Abietinean features, can NOT be taken as evidence of the 
Abietinean origin of the Araucarineae now living in Australasia. It is 
millions of years younger than other fossils with true and normal Arau- 
carian characters, from many parts of the world. 
It is, however, highly suggestive of the view that an extinct group 
of unexpectedly Abietinean affinity inhabited parts of the Southern Hemi- 
sphere in the Mesozoic epoch. 
Palaeobotany is beginning to accustom botanists to the idea that 
Australasian forms, Araucaria itself for instance, inhabited this country 
and Northern Europe in Mesozoic and Tertiary times. We must now 
prepare to entertain the reverse idea, that in the past the typically northern 
types of Conifers were inhabiting New Zealand at about the same time. 
Whether or not Planoxylon Hectori was directly Abietinean in its 
affinity, it was much more closely allied in the structure of its wood to 
living Abietineae than is any form now endemic in Australasia so far 
as is at present known. 
Summary. 
1. A petrified tree-trunk of not less than 150 seasons’ growth is 
described from the Cretaceous of Amuri Bluff, New Zealand. 
2. Its medullary ray cell-walls are thickened and pitted with typical 
‘ Abietinean * pitting ; and it has also wood parenchyma between the spring 
and last-formed wood of the previous season. 
3. Its spring tracheides have three rows of hexagonally compressed 
adjacent bordered pits; the next formed elements have groups of round- 
bordered pits ; and the last-formed elements have pits in single rows. 
4. It is very similar to Pence Lindleii of Witham, the detailed structure 
of whose rays is now described for the first time. 
5. The new wood and Witham’s species are placed in a new genus, 
Planoxylon , which is diagnosed on p. 119. It is recognized that it may be 
an extinct genus of unknown affinity, or may be more closely allied to the 
Abietineae than can be at present proved. 
6. It is probable that Gothan’s Cedroxylon transiens and Paracedroxylon 
araucarioides should also be included as further species of this genus. 
7. The new fossil Planoxylon Hectori is particularly interesting as 
