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scientific investigation. It was observed by Lemoine (1869) 
that when A. striatum Thompsonii was grafted on plants of A. 
megapotamicum and A. venosum the variegation spread into the 
green branches of the stock. Lindemuth (1897 to 1907) and Baur 
(1904-1906) ia) have greatly extended the knowledge 
of the nature of the variegation. The variegation is readily 
transferred by grafting to about fifty species and varieties of 
butilon or eae related forms with, however, some difference 
in the degree of susceptibility. At least certain strains of two 
species, pee arboreum and Lavatera arborea, are considered 
immune. Applications or injections of sap extract do not in any 
case produce the chlorosis. The infection occurs in susceptible 
plants only through direct grafting with infected plants, and is 
not transmitted through seed to progeny. 
Baur ae developed the theory that the variegation is 
sed by a virus which is produced in variegated leaves in the 
presence of light and alk carries the infection into newly 
formed leaves. Also that in each yellow variegated plant the 
virus is sufficient to infect only two or three newly formed leaves 
at one time; this amount is consumed by the continued growth 
of leaves, so that new leaves are green if the production of new 
virus is prevented. In no sense does he consider the ren 
of this virus being a parasitic organism. He considers that 
can either be a growth product of the ste plant increased . 
contact with the material within the plant cells, or a chemically 
highly organized material, itself capable of growt! 
The type known as Abutilon megapotamicum variegatum first 
originated in 1869 from grafting the pure green species with A. 
striatum T, hie as pene 1869). e Abutilon mega- 
potami n the trade is quite true to the original 
ype: although tans with a slightly different habit of growth 
and larger leaves are given different trade names. One of these 
is the Abutilon Eclipse, a plant which grows more erect and has 
larger leaves than the true Abutilon megapotamicum variegatum. 
The latter has a somewhat trailing habit of growth, making it 
very suitable for use in hanging baskets. Its leaves are narrow 
and lanceolate, brightly variegated with yellow flecks scattered 
