22 BULLETIN 30, PORTO RICO EXPERIMENT STATION. 
following September, or two years from setting, the maximum 
height attained was 119 inches, the average height was 59 inches,, 
and a number of trees were over 7 feet. (PL VIII, fig. 2.) Fur- 
ther measurements were not made as topping at about 8 feet was 
begun within the year. Unless they are topped the trees will soon 
make such vigorous growth as to render picking difficult. The lat- 
eral branches are rather delicate. Representative lengths are 2J to 
4J feet, although some exceed this. The internodes on laterals range 
in length from 2 to 6 or more inches, with an average of 3 or 4 
inches. The leaves of the various individuals vary somewhat in 
shape, some being oval with obtuse base and apex having acuminate 
tip, and others being elliptical with acute base and apex. In length 
they may range from 6 to 12 inches, but generally are 7 to 10 inches. 
The length ranges from less than twice to nearly three times the 
breadth. The leaf texture is not so heavy as in the Liberian group, 
and the leaves are subject to attacks by the leaf miner. 
The blossoms are white, five or six petaled, and from 1^ to 1£ inches 
across. They appear at irregular intervals, and may be seen on the 
trees simultaneously with green and mature cherries. (PL X, fig. 2.) 
The ripening season for the three plantings is given in Table ]L 
In common with the other members of this group the crop began to 
ripen in October, but ripened mainly in the winter months, nearly 
half maturing in January and the rest in the spring. Only a negligible 
quantity of cherries ripened in the fourth year from seed. The yields, 
which are shown in Table 6, have been surprisingly low for a coffee 
celebrated elsewhere for its productivity. The cherries are closely 
clustered, there being 15 to 30 or more at a node. (PL IX. fig. 2.) 
When ripe they are blood red, some being of solid color and others 
finely striped in dark and light red. Striping is less conspicuous 
when the cherries are very ripe. Occasionally the navel is flat, but 
more frequently it protrudes, and the pulp is very thin. The cherry is 
smaller than that of the Arabian coffee, representative specimens be- 
ing 14 millimeters long, 13 millimeters in the diameter at right angles 
to the flat faces of the beans, and 10 to 11 millimeters in the other 
diameter. Five samples showed between 528 and 630 cherries per 
liter with an average of 564. Two almuds of freshly picked Robusta 
cherries weighed 28 pounds 11 ounces and 29 pounds 9 ounces, respec- 
tively. The latter gave 6 pounds 12 ounces of cleaned marketable 
beans, a reduction in weight in the ratio of 4.4 to 1. Two samples 
were found to contain 2,726 and 2,736 beans per pound, respectively, 
showing the beans to approximate the Porto Rican coffee in weight, 
though it differs from the latter in its more rounded form. The silver 
skin is brownish and rough in appearance, and adheres closely to the 
bean. It does not clean off readily after slow drying in the sun, but 
is effectively removed when rapidly dried by artificial heat. The bean 
does not present an attractive appearance unless the silver skin is 
thoroughly removed. 
Canephoba. 
Considerable variation between individuals is found in the station 
plantings of Coffea ccmephora, The range is from the type showing 
narrower leaves or more flattened cherries than those of the typical 
C. robusta to others which are wholly indistinguishable from O. ro- 
busta in habit, foliage, and appearance of cherry. This is perhaps 
