This section is from the book "The Standard Cyclopedia Of Horticulture Vol2", by L. H. Bailey. See also: Western Garden Book: More than 8,000 Plants - The Right Plants for Your Climate - Tips from Western Garden Experts.
(Limonia § Citropsis, Engler). Rutaceae. African Cherry Orange. Very interesting and as yet little-known citrous trees, of interest for use in hybridizing and for stocks, also promising as ornamentals.
Small spiny trees: leaves compound, 3-12 in. length; leaflets 3, 5 or even 7, coriaceous; petioles and rachis usually very broadly winged; fruiting twigs sometimes with unifoliate leaves: spines usually paired, sometimes single: flowers large, white, in the axils of the leaves, tetramer-ous (rarely 5-merous), with 8 free stamens: fruits small, 3/4-l 1/2 in. diam., borne in tufts in the axils of the leaves, bright orange-colored, with an agreeable odor and a pleasant flavor, 3-4-celled, with a single seed in each cell; cells in some species filled with pulp-vesicles full of pleasantly flavored juice.
There are several species of this interesting genus in the tropical forests throughout central Africa. These plants, because of their sweet high-flavored fruits borne in tufts like cherries and their unusually large compound leaves, should prove very interesting for use in hybridizing. Tests made in the greenhouses of the Department of Agriculture, at Washington, have shown that at least two species of Citropsis can be budded readily and grow very well on the common citrous stocks. This genus is undoubtedly closely related to Citrus. See descr. in Journ. Ag. Research, 1:419-436, w. figs.
Preussii, Swingle & M. Kellerman (Limonia Preussii, Engler. L. Demeusei, De Wild?). Leaves 3-5-foliate, with very broadly winged petioles and rachis; leaflets large, broadly oval: flowers large, axillary; style long, slender, broad at the base: fruits small, apiculate. Kamerun. W.Congo. 111.Engler & Prantl, Nat. Pflanzf. III. 4:189, fig. 109, E. H. De Wildeman, Etudes Flower Congo, pl. 41.
Schweinfurthii, Swingle & M. Kellerman (Limonia Schweinfurthii, Engler. Limonia ugandensis, Baker). Fig. 972. A species named from sterile leafy twigs collected by Schweinfurth at Uando at the headwaters of the Ghazal branch of the Nile. Leaves 3-5-foliate; leaflets narrowly lanceolate, acute at both ends: flowers large, usually 4-merous; style rather short and thick: fruits lime-like, 1 1/2 in. diam., sweet. Sudan, Uganda, Congo.
Fig. 972. Citropsis Schweinfurthii. (X 1/4)
Swingle & M. Kellerman (Limonia gabonensis, Engler). Leaves of medium size, sometimes unifoliate like orange leaves, sometimes 5-7-foliate; rachis narrowly winged; leaflets caudate: flowers small, borne on long pedicels, 4-merous; style not broad at base: fruits globose, small, about 1 in. diam., almost dry, having only rudimentary pulp-vesicles; seeds large. French Congo, Kamerun.
Walter T. Swingle.