g6 Parasitic Arthropoda 



Only the females suck blood. They attack not only man but all 

 warm-blooded animals and, according to recent workers, also cold- 

 blooded forms, such as frogs, lizards, and larvae. Indeed, Townsend 

 (19 1 4) believes that there is an intimate relation between Phlebotomus 

 and lizards, or other reptiles the world over. The Phlebotomus 

 passes the daylight hours within the darkened recesses of the loose 

 stone walls and piles of rock in order to escape wind and strong light. 

 Lizards inhabit the same places, and the flies, always ready to suck 

 blood in the absence of light and wind, have been found more prone 

 to suck reptilian than mammalian blood. 



On hot summer nights, when the wind is not stirring, the Phleboto- 

 mus flies, or sand-flies, as they are popularly called, invade houses and 

 sleeping rooms in swarms and attack the inmates. As soon as light 

 begins to break the flies either escape to the breeding places, or cool, 

 dark places protected from the wind, or a part of them remain in the 

 rooms, hiding behind pictures, tmder garments, and in similar places. 

 Wherever the Phlebotomus flies occur they are an intolerable nui- 

 sance. On account of their small size they can easily pass through 

 the meshes of ordinary screens and mosqvtito ctirtains. They attack 

 silently and inflict a very painftil, stinging bite, followed by itching. 

 The ankles, dorsum of the feet, wrists, inner elbow, knee joint and 

 similar places are favorite places of attack, possibly on account of 

 their more delicate skin. 



Special interest has been attracted to these little pests in recent 

 years, since it has been shown that they transmit the European 

 "pappatici fever" or "three day fever." More recently yet, it 

 appears that they are the carriers of the virus of the Peruvian "ver- 

 ruga." This phase of the subject will be discussed later. 



Control measures have not been worked out. As Newstead says, 

 "In consideration of the facts which have so far been brought to light 

 regarding the economy of Phlebotomus, it is clearly evident that the 

 task of suppressing these insects is an almost insurmountable one. 

 Had we to deal with insects as large and as accessible as mosquitoes, 

 the adoption of prophylactic measures would be comparatively easy, 

 but owing to the extremely minute size and almost flea-like habits of 

 the adult insects, and the enormous area over which the breeding- 

 places may occur, we are faced with a problem which is most difficult 

 of solution." For these reasons, Newstead considers that the only 

 really prophylactic measures which can at present be taken, are those 

 which are considered as precautionary against the bites of the insects. 



