28 BOTANICAL GAZETTE [JULY 
R. tsugensis is not confined to species of Tsuga as heretofore 
believed, but will infect Adzes lasiocarpa. The mistletoe most 
closely resembling R. tsugensis in point of color and size is the form 
R. occidentalis abietina, but as the results from cultures stand at 
present there is apparently no relation between them. ‘The fore- 
going results indicate that the plant occasionally found on firs in 
the same vicinity with R. tsugensis is the common hemlock mistletoe, 
Fic. 18.—R. tsugensis on Tsuga heterophylla: staminate and pistillate plants; 
large form. 
and also that this species may be expected to occur occasionally on 
other hosts than hemlock. Cultures may be considered fully 
completed when the plants found on Abies in the vicinity of R. 
tsugensis, also the form on Abies which has been referred to the 
yellow pine mistletoe, are shown by culture to infect Tsuga and 
Pinus respectively. 
SUMMARY.—Seeds were also sown on Abies grandis, Pinus 
ponderosa, Picea orientalis, Larix occidentalis, and Pseudotsuga 
taxifolia, but the results were negative. The hosts of Razoumofskya 
