M. s. Riversii. 
M. toringoides. W. China. 
M. Tschonoskii. Japan. 
M. yunnanensis. W. China. 
M. y. Veitchii. C. China. 
M. Zumi (M. baccata mandshurica x Sieboldii). Japan. 
MAMMILLARIA, Cactaceae. A spiny cactus with yellow to 
reddish flowers, thriving on sandy soil and in full sunlight [5E]. 
M. missouriensis (Neobesseya m.). S. D. to Tex. and Colo. 
MARSDENIA, Asclepiadaceae. A sun-loving rambling shrub 
with clusters of white flowers; it may be trained up a wall to 
advantage [nursery]. 
M. erecta. S.E. Eu., W. Asia (Jn.). 
MENZIESIA, Ericaceae. A shrub similar in appearance to Vac- 
cinium but of less ornamental value [nursery]. 
M. glabella. B. C. to Minn, and Wyo. 
MESPILUS, Rosaceae. Medlar. A small tree not unlike Cratae¬ 
gus in habit and with edible fruit [6J]. 
M. germanica minor * (My.). 
MITCHELLA, Rubiaceae. Partridge-berry. A prostrate ever¬ 
green with trailing stems and small red berry-like fruits. It 
grows best in partial shade where moisture is abundant [5E]. 
M. repens. N. S. to Fla. and Tex. 
MOLTKIA, Boraginaceae. A low shrub with violet-blue 
flowers. Of interest to the collector of rock-garden plants [5E]. 
M. petraea. S.E. Eu. (Jn.). 
MORUS, Moraceae. Mulberry. Rounded trees that bear sweet 
* M. germanica is native from southeastern Europe to Persia. 
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