1900] von Schrenk, — Notes on Arceuthobium pusillum 5 
the stems bend toward the newer branches as the seeds ripen. This 
was very marked on the spruces about Linekin. ‘Towards the latter 
part of September, the stems became inclined towards the outer part 
of the tree. This brought the axes of the berries into a line almost 
parallel with the branch upon which the plants grew, i. e., with the 
ends from which the seeds were to fly toward the outside of the tree. 
-The last week in September, the berries were ripe, and every day the 
seeds were shot out, flying out upon the newer branches. The manner 
in which the spirally marked hairlike cells glue the seeds to the bark 
will later be described more in detail. 
The longitudinal arrangement of the stems on a branch has given 
rise to the supposition that they spring from longitudinal rhizomes, 
which grow in the bark of the host. This system of rhizomes is a very 
complex one. A network of threads grows out from the base of each 
stem, one thread fusing with another before long. From these threads 
the actual absorbing organs, the haustoria, are developed much as in 
the true mistletoes. 
The distribution of this mistletoe is an interesting one. There 
seems to be little doubt now that birds in some cases carry the seed 
from place to place, for they must have carried them to Monhegan 
Island. Its occurrence in moist swamps and along the coast has been 
alluded to, and it is to be hoped that collectors in the New England 
States will watch for the plants, that we may be able before long to 
establish a complete chain from its furthest western to its most eastern 
station. Specimens will gladly be supplied on application. 
SHAW SCHOOL or BOTANY. 
EXPLANATION OF PLATE 12.— Fig. 2. Horizontal branch of white spruce, Picea 
Canadensis, B. S. P. (P. alba, Link) with very young witches’ broom. ‘The latter is 
two years old. Note the strong buds on the branches of the broom, both terminal 
and lateral. About one-fourth natural size. Fig. 1. Older witches’ broom of the white 
spruce. The stems of the Arceuthobium cover the branches, but are too small to be 
visible in the photograph. Note how the terminal part of the main horizontal branch 
is dying, also how the main stem of the broom is now thicker than the original host 
branch. Note the length of the annual growth of the broom branches, compared 
with that of the host branch, About one-fourth natural size, 
