22 BULLETIN 55, HAWAII EXPERIMENT STATION 
casionally found feeding upon the foliage of the plant. Damage 
from fungus diseases, the banana freckle disease excepted, is neg- 
ligible. The cane borer (Sphenophorus obseums) is no longer a pest 
of the banana plant in Hawaii, having been almost completely ex- 
terminated by the tachinid fly Ceromasia sphenophori, which was 
introduced into Hawaii in 1910 by the Sugar Planters' Association 
Experiment Station to check the ravages of the pest. 
The mealybug Pseudococcus bromelim is found in masses between 
the fruits in some localities during the drier months of the year, and 
although it does not seriously retard development of the fruit it 
does make it unclean. The pest may be removed by washing the 
severed bunches with streams of water from a force pump. P. bro- 
melice also attacks young suckers and injures them considerably; 
and it collects under the leaves and the inner side of the outer 
sheaths where it feeds upon the sap, greatly retarding growth. The 
pest may be controlled by spraying with an oil emulsion. 
Notwithstanding the investigations made since 1910 to determine 
to what extent the banana in Hawaii is attacked by the Mediter- 
ranean fruit fly {Ceratitis capitata), no evidence has been obtained 
indicating that commercial varieties are susceptible to attack by the 
pest. This fact has failed to receive the publicity to which the 
banana industry is justly entitled. 
When the Mediterranean fruit fly was discovered to be well estab- 
lished in Hawaii, the Bureau of Entomology of the United States 
Department of Agriculture, at the request of the Federal Horticul- 
tural Board, began an investigation covering three years (1912-1915) 
to learn which fruits should be prohibited from exportation. A 
summary of the findings (3) in so far as the banana is concerned 
and a report (4) of the field work done were published later. It is 
to be regretted that the investigators did not have at the time a 
clear classification of all the banana varieties growing in Hawaii so 
that each variety could have been fully tested to determine its 
susceptibility to fruit-fly attack. The report of the possible infec- 
tion of two thin-skinned native varieties, the Popoulu and the Moa, 
when allowed to ripen on the plants, has probably led uninformed 
persons to believe that all Hawaiian varieties are attacked by the 
Mediterranean fruit fly. The Popoulu and Moa varieties are rarely 
eaten raw or shipped from the islands. They are scarce and are 
strikingly distinct from both ordinary cooking bananas and the 
commercial varieties. 
Examination of approximately 27,000 fruits of the Chinese variety 
in the Moanalua fields, Oahu, in 1913, showed no evidence of fruit-fly 
infestation or of egg puncture. Examination of 3,-500 bananas of 
the same variety at Kalauao, Oahu, gave negative results, and 1.000 
bananas of this variety which were considered too mature for ship- 
ment gave no evidence of fruit-fly infestation when held in the insect 
hatchery of the laboratory. A lot of 1,044 bananas discarded for 
similar reasons gave negative results when examined in the labora- 
tory. Fully ripened fruits of the Chinese and Apple varieties grow- 
ing among many other kinds of fruits showed no evidence of infesta- 
tion, and some 50 fruits of the Ice Cream variety, cut in 1914 from 
