28 BULLETIN 134, U. S. DEPARTMENT OF AGRICULTURE. 
Italy. Most of the olives attacked fall to the ground before reaching 
maturity. In the case of the olive fly, mature fruit is not at all 
necessary for infestation. Because of the economical use made of 
all the inferior fruit in these countries — something we have yet to 
practice — infested olives are not a complete loss, for they are used 
for oil, most of which is used in the manufacture of soap. The 
striking difference in habits between the olive fly and the Medi- 
terranean fruit-fly is that, with the former, pupation occurs within 
the fruit, instead of in the ground or otherwise out of the fruit as is 
the case with Ceratitis. 
Infested olives may be distinguished by a circular area on the 
surface that is of a light gray color. Before entering the pupal stage 
the larva eats out a chamiel to the surface of the fruit, leaving only 
the thin epidermis. It is this, with the tissue eaten away below, 
that forms the characteristic gray area that indicates infestation. 
It is much the same as that made in the case of the pea and bean 
weevils. Having completed the burrow to the surface, the larva 
retreats a short distance and transforms to the pupa, enclosed in the 
characteristic puparium, that looks much like that of Ceratitis. 
Upon emerging the adult fly breaks through the epidermis, which 
has been left for protection, by means of its ptilinum. 
Fortunately olives are not transported unless pickled, and thus 
the danger of introduction is not great, But a sharp lookout should 
be kept for any olives that might possibly be imported fresh from 
these countries, since the egg, larval, and pupal stages are all passed 
within the fruit . 
THE MEDITERRANEAN CITRUS FRUIT INDUSTRY. 1 
SPAIN. 
LOCATION. 
The most important citrus section of Spain, where 90 per cent of 
the crop is produced, consists of a narrow strip, 10 or 15 miles wide 
and 150 miles long, extending from Denia in the Province of Alicante 
northward as far as Yinaroz in the Province of Castellon. This is 
the so-called "Valencia section," the city of Valencia being situated 
somewhere near the center of the strip. In this section are recog- 
nized two distinct districts, the "Ribera" and the "Plana." The 
"Ribera" lies to the south of Valencia and centers chiefly about the 
towns of Alcira and Care agent e. This district is more or less rolling 
and hilly and is separated from the sea, which is 15 or 20 miles 
distant, by hills and mountains. The "Plana" lies north of the 
City of Valencia and centers about the town of Burriana. This is a 
perfectly flat plain and borders directly on the sea. Around the 
1 In this account of the Mediterranean citrus industry only such phases are presented as are necessary 
to a better knowledge of the insects discussed in the earlier pages of this paper. 
