OF THE MALTESE ISLANDS. 



63 



longitudinal is simple, and unites with tlie costa aboTit 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 fom-th 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 foiu'th ; while the supernumerary vein is placed immediately above it, and 

 j)asses obli([uely to 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 Morphology, 

 The Alimentary Canal (fig. 8). 



This structure diffei's from that of the mosfjuito 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. 



Scufellum 



Fig. 8. — Internal morphology of Phlebolomus. 



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, 



