OF THE MALTESE ISLANDS. 63 
longitudinal is simple, and unites with the costa about one-third from the tip : 
the second longitudinal is twice forked, and extends almost to the base of the 
wing ; the third longitudinal is simple, and originates from the mid cross-vein ; 
the fourth has origin at the base of the wing and is forked near the middle ; 
the fifth and sixth are simple and united basally, the former curving upwards 
and uniting with the fourth considerably in advance of the base of the 
wing. The first cross-vein unites the costa with the sub-costa at a point 
immediately opposite to the turned-down portion of the latter, so that in effect 
they produce two cross-veins: the first extending from the first longitudinal vein 
to the sub-costa, the second from the tip of the latter to the costa. The mid 
cross-vein arises from the base of the third longitudinal and passes obliquely to 
the fourth ; while the supernumerary vein is placed immediately above it, and 
passes obliquely te the second longitudinal. 
Legs.—These are very long and slender and densely clothed with scales, 
the majority of which are flat and closely resemble those which are found in the 
CuLICIDAE. The ungues are simple in all of the Maltese species, and do not 
offer any differential morphological characters. 
INTERNAL MorrpHoLoey, 
The Alimentary Canal (fig. 8). 
This structure differs from that of the mosquito in having a true sucking 
stomach, and also in the possession of four Malpighian tubules instead of five. 
The general form and relative position of these organs in the female are as 
follows :— 
The buccal cavity lies at the base of the clypeus; it is dilated distally, but 
almost immediately contracts and forms a slender tube which leads to the 
pharynx. 
Scutellum Sucking 
stomach 
Fig. 8.—Internal morphology of Phlebotomus. 
The oesophagus divides at a point a little in advance of the posterior margin of 
the head (nape), one tube leading to the sucking stomach, or food-reservoir, the 
other to the digestive canal, 
