Marusho Motor Co., Ltd,
Marusho Motor Co., Ltd, (Hamamatsu City, Shizuoka) manufactured the Marusho and Lilac line of motorcycles. These were mainly shaft drive twins (both V and flat twins) and singles which were manufactured between 1950 and 1961, and then again (after recovering from bankruptcy) from 1963 till 1967. The final R92 500cc model produced in 1966 had electric start and a handful were imported into the USA under the Marusho Magnum name.
Over the course of production some 31 different models of Marusho/Lilacs were built having displacements ranging from 50cc through to 500cc. At its peak, total production was about 11,000 units per year in 1959.
The best on-line source of information I've found for Lilacs is this site. It isn't maintained, but as of the time of writing was still alive.