December, ’20] RIXFORD: SYMBIOSIS OF BLASTOPHAGA and FIGS 459 
Mr. M. L. Dean defined the special duties of the state officials and 
stated that the help of all was needed to accomplish the desired results, 
promising in return complete cooperation. 
He also showed some very fine specimens of the egg masses of the 
fruit tree leaf roller, Archips argyrospila Walk., on apple twigs taken 
from the Bitter Root Valley, Montana. 
A full discussion followed. 
Chairman A. L. Melander: The next paper is entitled “Sym¬ 
biosis of Blastophaga and the Fig Family. ” 
SYMBIOSIS OF BLASTOPHAGA AND THE FIG FAMILY 
By G. P. Rixford, United States Department of Agriculture 
The great fig family, Ficus of the order Moracese, is one of the 
largest of the vegetable world. Botanists have identified and described 
more than six hundred species. Most of them are tropical evergreens, 
frequently of gigantic size, often parasitic or epiphytic. Fraser, 
speaking of the Morton Bay figs of Australia, said, “I observed several 
species upwards of a hundred and fifty feet high, enclosing immense 
iron-bark trees, on which seeds of the fig trees had been originally 
deposited by birds. Here they had vegetated and thrown out their 
parasitical and rapacious roots, which, adhering close to the bark of 
the Iron-tree, had followed the stem downward to the earth, where, 
once arrived, their growth was astonishing. The roots increase rapidly 
in number, envelope the Iron-bark, and send out at the same time 
gigantic branches, so that it is not unusual to see the original tree, at 
the height of 70 or 80 feet, peeping through the fig as if it were a parasite 
on the real intruder.” The writer has seen the same thing in the 
tropics of Central America, where the giant fig had strangled the host 
to death, after which the rapid decay in the moist tropics allowed the 
torrential rains to wash out the decaying wood through openings in 
the enveloping fig, until the final result was a giant cylinder, 6 to 8 
feet in diameter and 75 to 100 feet in height and 6 inches thick, still 
vigorously flourishing. The natives called it Matar Palo (tree killer). 
Other notable forms are the Banian tree, F. benghalensis, which sends 
down aerial roots or branches into the soil where they take root and 
form new trunks. The Banyan, under which Alexander camped is 
said to have sheltered 7,000 men, now measures 2,000 feet in circum¬ 
ference and has 3,000 trunks. Another important member of the 
genus is Ficus elastica, a rubber tree. A popular climber in California 
is F. repens, used for covering brick and other walls. Another remark¬ 
able species, native of South Africa, produces its fruit under ground. 
It is thought by some authorities that each Ficus species has its own 
