_Arnoldiana_, a species near to _Coffea Abeokutæ_ having darker foliage and the even colored small berries;
_Laurentii Gillet_, a species not to be confused with the _C. Laurentii_ belonging to the _robusta_ coffee, but standing near to _C. liberica_, characterized by oblong rather than thin-skinned berries;
_Excelsa_, a vigorous, disease-resisting species discovered in 1905 by Aug. Chevalier in West Africa, in the region of the Chari River, not far from Lake Tchad. The broad, dark-green leaves have an under side of light green with a bluish tinge; the flowers are large and white, borne in axillary clusters of one to five; the berries are short and broad, in color crimson, the bean smaller than _robusta_, very like _Mocha_, but in color a bright yellow like _liberica_. The caffein content of the coffee is high, and the aroma is very pronounced;
_Dybowskii_, another disease-resisting variety similar to _excelsa_, but having different leaf and fruit characteristics;
_Lamboray_, having bent gutter-like leaves, and soft-skinned, oblong fruit;
_Wanni Rukula_, having large leaves, a vigorous growth, and small berries;
_Coffea aruwimensis_, being a mixture of different types.
[Illustration: COFFEA ARABICA BERRIES GROWN IN THE HAWAIIAN ISLANDS]
The last three types were received by Dr. Cramer at Bangelan from Frère Gillet in the Belgian Congo, and were still under trial in Java in 1919.
Emil Laurent, in 1898, discovered a species of coffee growing wild in Congo. This was taken up by a horticultural firm of Brussels, and cultivated for the market. This firm gave to the coffee the name _Coffea robusta_, although it had already been given the name of the discoverer, being known as _Coffea Laurentii_. The plant differs widely from both _arabica_ and _liberica_, being considerably larger than either. The tree is umbrella-shaped, due to the fact that its branches are very long and bend toward the ground.
The leaves of _robusta_ are much thinner than those of _liberica_, though not as thin as those of _arabica_. The tree, as a whole, is a very hardy variety and even bears blossoms when it is less than a year old. It blossoms throughout the entire year, the flowers having six-parted corollas. The drupes are smaller than those of _liberica;_ but are much thinner skinned, so that the coffee bean is actually not any smaller. The drupes mature in ten months. Although the plants bear as early as the first year, the yield for the first two years is of no account; but by the fourth year the crop is large.