8 Rhodora [JANUARY 
parts of the host or other plants in the vicinity, upon which they ger- 
minate, under favorable conditions. 
The manner of seed expulsion in this genus, as seen in some wes- 
tern species, has been described by D. T. MacDougal in Minnesota 
Botanical Studies, 2nd series, part ii., February 22, 1899, p. 169—173. 
No opportunity was obtained for observing the actual expulsion of 
seed from the Boylston plants, but this was seen very well in fresh 
specimens growing on white spruce in Maine, kindly furnished by Dr. 
Hermann von Schrenk. 
The mistletoe at Boylston, as yet the only known locality for it in 
Massachusetts, is now nearly extinct, and will soon be completely erad- 
icated, because, in the summer of 1898, the host-plants and other trees 
and shrubs were cut and burned to clear the ground for surveyors, 
and only a few small fragments of the mistletoe-bearing host escaped 
alive. These will soon be obliterated, because the swamp is to be filled 
or thoroughly cleaned out, and the pure waters of the reservoir will 
eventually flow over it. 
This Arceuthobium may be found in other localities not far away. 
In looking for it, the hunter will be aided by the fact that the affected 
host-plants often appear distorted or stunted in comparison with per- 
fectly healthy trees. 
In the accompanying plate, generously furnished by Mr. C. E. 
Faxon, the figures have been drawn from specimens growing on black 
spruce collected in the Boylston locality. 
ARNOLD ARBORETUM. 
EXPLANATION OF PLATE 13.— Arceuthobium pusillum, Pk. Fig. 1, branch of 
black spruce in spring, with staminate Arceuthobium in flower; a, twig one year 
old; 4, twig two years old ; c, twig three years old. Fig. 2, branch in autumn with 
pistillate plants and fruit; a, twig one year old; 4, twig two years old showing buds 
of the parasite ; c, twig three years old with full-grown Arceuthobium ; æ, twig four 
years old with fruiting plants. Fig. 3, plant with mature fruit, Fig. 4, staminate 
plant in flower. Fig. 5, pistillate plant in flower. Fig. 6, staminate flowers. Fig. 7. 
pistillate flowers. Fig. 8, the same in vertical section. Fig. 9, fruit, showing manner 
of dehiscence and seed expulsion. Fig. 10, seed. (Figs. 1 and 2, natural size; figs. 
3 to 10, enlarged.) 
ARCEUTHOBIUM PUSILLUM ON A NEW HOST IN VERMONT. — I have been 
confident for several years that Arceuthobium pusillum, PK., must occur 
in Vermont. The black or swamp spruce, its usual host, is common in 
the sphagnum swamps of the Champlain valley and elsewhere in the 
state. Professor Peck finds the Arceuthobium in the Adirondack 
