16 BULLETIN 30, POKTO RICO EXPERIMENT STATION. 
The Liberian coffee at the station was derived from various 
sources. With the exception of three trees, set in 1910 when small, 
the main planting of 77 trees is from seed sown between October, 
1911. and January, 1912. In July, 1913, the trees were transplanted 
to the field, and each Julv thereafter annual measurements of their 
height were made. The trees transplanted in 1913 averaged 13£ 
feet in height in 1919. The maximum height in 1922 was 20-J feet. 
The tallest of the three trees set out in 1913 was 26 J feet in 
July, 1922. 
Trees of the Liberian group are of upright rather than of spread- 
ing habit, with stiff, straight trunks. The internodal length, while 
extremely variable, is greater than that in the Arabian group, the 
longer internodes on uprights even exceeding a foot in length. The 
leaves also are larger, oval or elliptical in shape, typical specimens 
measuring 6 to 12 inches in length by 2J to 6 \ inches in breadth, 
and are stiff and leathery in texture. Van Zwaluwenburg 29 states 
that " some varieties of coffee seem to be practically immune to miner 
injury due to the thickness of their leaves; among these are the 
Liberian coffee and several other species belonging to the same 
group." A miner may enter a leaf, but it will hardly make much 
headway. The flowers are large and white, and have six to eight 
petals. 
Most of the crop of this variety in Porto Rico is harvested from 
December to March, inclusive, with the heaviest ripening in January, 
with February second. At five years from seed about three-eighths 
of the trees were producing a few cherries, but the total yield was 
negligible. During the sixth year three-fourths of the trees were 
producing. The average yield for the planting, in fresh cherries 
per tree, is given in Table 6. * 
In color, the cherry is finely striped in dull red and light yellow 
(straw), with the red predominating. The disk is russet and in 
some specimens very broad and prominent. The cherries are borne 
singly and in small clusters rather than in densely crowded clusters 
like those of Excelsa or the Robusta group. The skin and pulp 
differ from those of the Arabian in that they are very thick, stiff, 
contain less juice, and form a much larger proportion of the fruit. 
In an almud freshly pulped the ratio by weight of pulp to coffee 
in parchment was a little over 8 to 5. The parchment is more woody 
and darker in color than that of the Arabian, and while the reduction 
in weight through removal of the parchment of the Arabian may 
run from 15 to 20 per cent, it amounted to 33 per cent in a sample 
of Liberian, which was the heaviest reduction in any of the coffees 
compared. 
There is a wide range in size of Liberian cherries. A liter of 
cherries selected for size was found to contain 68 large specimens, 
or 214 small ones. Two liters were found to contain 132 and 141, 
respectively, of unselected cherries. An almud of cherries which 
weighed 28 pounds 1 ounce before pulping, gave 4 pounds 1 ounce 
of dry coffee in parchment. After the removal of the parchment 
there remained only 2 pounds 12 ounces of marketable coffee, the 
total reduction in weight being 10.2 to 1, which was the most un- 
36 Insects affecting coffee in Porto Rico. R. H. Van Zwaluwenburg. Jour. Bcon. Ent., 
rol. 10, No. 6 (1917), p. 514. * 
