422 Farr on British Columbian Plants. 
As originally defined by Rafinesque and Pursh it is 
scarcely possible accurately to determine which of the above 
species is intended from the descriptions, since the salient 
points of distinction are entirely overlooked. In the more 
recent descriptions of Trelease and Howell, and also from 
the study of specimens distributed by Howell, the specific 
name Myrsinites should be restricted as above given. The 
flowering period of both is about the middle of June. 
Although not included in the definition there seems a strong 
reason for believing that the flowers are gyno-monoecious, 
there being a few blooms with large protruding ovary and 
rather rudimentary stamens, while the majority of the flow- 
ers have well-developed stamens and a deeply-sunk recep- 
tacular ovary. Future study alone can settle these points. 
From all the material collected by the writer and examined 
in herbaria, the flowers of each succeeding season seem to 
develop in the preceding autumn, and remain in bud condi- 
tion throughout the winter, much as in Dogwood and Japa- 
nese Paulownia. A study and comparison of these forms 
over wide areas of Western North America is highly to be 
desired. 
In order to determine more accurately possible points of 
difference between these species, a histological study has been 
made with the following results: 
Pachystima Myrsinites, Raf.—Cork broad, black extern- 
ally in a broad zone, brown internally in a rather narrower 
zone. Cortex with few conglomerate crystal cells, scleren- 
chyma strands in the collenchyma feeble or mostly absent. 
Sclerenchyma elements of inner cortex scattered in patches of 
eight to five or even solitary, but in a pretty continuous line. 
Wood dense. Pith cells all heavily indurated; abundantly 
starch-storing. Leaves with lower epidermal cells one-third 
smaller than next, walls straight or slightly wavy and stomata 
relatively abundant; the median vascular bundle of the mid- 
rib with a sclerenchyma strand beneath the phloem that is 
comparatively small in amount, leaf below the strand flat and 
with epidermal cells scarcely swollen. 
