Igo Crais—A NEw CHINESE PsSEUDOTSUGA. 
verse sections of the leaf. In the former hypodermis is developed 
only in the median plane of the leaf and very sparsely at the 
margins. Occasionally one or two solitary cells may be found 
along the upper surface between the margin and the midrib. 
In P. sinensis, on the other hand, there is a well-marked con- 
tinuous or almost continuous hypodermis. And again, the 
epidermal cells of P. Forrestii tend to be decidedly deeper than 
broad, whereas those of P. sinensis are almost as broad as deep. 
P. sinensis and P. Forrestii are two closely allied species 
which form a geographically and systematically distinct sub- 
genus. A first examination of the cone of either species recalls 
from the consistency of the scales the genus Keteleeria, the 
bracts alone reminding one of Pseudotsuga. The leaves and 
buds agree well with Pseudotsuga. Leaf-anatomy also supports 
their subgeneric rank. In the leaves of both species we find 
rayed idioblasts and infoldings of the cell-wall of the spongy 
tissue. In both these characters they differ from the true 
Pseudotsuga. The presence of rayed idioblasts is admittedly 
not of generic importance, e.g. some species of Abies develop 
them but in many more they are absent. But the presence of 
the infoldings of the cell-wall has been regarded as of generic 
rank. The infoldings are not so uniform as in Pinus, and in 
the material examined I failed to detect them in the palisade 
tissue. But they do form quite a marked feature of the spongy 
tissue of the leaf of P. sinensis and of P. Forrestii. 
Sections of the oldest available branches on the herbarium 
specimens of Forrest, 13,003, show the distinctive anatomical 
features associated with the wood of the genus Pseudotsuga. 
Of the other two Asiatic species of the genus sufficient 
material is not yet available. Of P. japonica there are several 
young plants in cultivation here, and Sir E. Loder has also sent 
a fragment of a cultivated plant. Leaf-sections from both 
sources show the same anatomical structure as found in P. 
Douglasit, i.e. leaf-sections made from young plants show no 
rayed idioblasts and no infoldings of the cell-wall. Of P. 
Wilsoniana* from Formosa I have seen no specimens. 
LIST OF PLATES 
Illustrating Mr. Craib’s paper on Pseudotsuga. 
Pirate CLX. Pseudotsuga Forrestii, Craib. Sp. nov. 
CLXI. Pseudotsuga sinensis, Dode. 
* Hayata in Icon. Plant. Formos., v (1915), 204, tab. xv. 
