CALIFORNIA CITRUS CULTURE. 85 
that its peculiar sourness and bitter flavor persists would seem to sustain 
this contention. It is, however, very similar to the sweet orange. Dr. 
G. Harold Powell informs me that the stock of the bitter orange is 
universally used in lemon growing in Italy. 
Fic. 57.—The sour or bitter orange (Citrus aurantium var. amara Linn. 
(After Lelong.) 
Citrus aurantium Linn. var. sinensis Engler. 
This is our common sweet orange and includes all the subvarieties 
so familiar to us. These subvarieties are often as marked as the variety 
itself. Its excellence and commercial importance makes it a great 
favorite, and so it is much grown and subject to varied care and treat- 
ment. This is doubtless the cause in great part of its many variations. 
Unaided nature has given us the superb navel orange. Does this not 
show that the orange is susceptible to change and improvement, in 
short, to marked bud variation? We believe we are safe in saying that 
the skillful breeder has great opportunity to create an orange that may 
greatly distance in excellence and productivity any yet produced. 
The leaves of the sweet orange are oblong and pointed, petiole nar- 
