A Mojiograph of Egyptian Diptera. 



numerous, seattered aucl rather distant; thèse show a passage iiito 

 the reticuhite type. In this type the wings should be considered as 

 black with numerous approximate hyaline spots, which break up 

 the black colouring into a net-like or reticulate pattern. This net- 

 work can be more or less tlosed owing to the forni and size of thèse 

 spots and sometimes quite broken up into brown isolated streaks. 

 The so-called "star-shaped" pattern and the "radiating" })attern 

 are spécial cases of this type. 



The colouring of the pattern varies from yellow or brown to 

 black; I fail to see any traces of red spots as stated liy Becker in 

 his original description of Schistoptentm. 



The adult flies are remarkable for their haudsome aspect and 

 coloration, chiefly due to the patterned wings which they usually 

 hold spread out and trembling; they may frequently be seen run- 

 ning on leaves or feeding on flowers. They usually prefer shady and 

 cool places, hence they are to be found on the under surface of broad 

 leaves. The species of Ceratitis and Dacus seek the sweet exuda- 

 tions and sécrétions of plants or of certain insects such as the Coc- 

 cidae (Scale-insects), but generally speaking the adults are to be 

 found on those plants in which they oviposit and upon which their 

 larvae feed. 



The Trypaneidae live only and entirely on vegetable substances, 

 some species being very serious pests. It is a remarkable fact that 

 many of the species which may easily be obtained and observed in 

 the larval stage, are rarely seen as adults, such as Ceratitis ca- 

 yitata Wied., Caipomyia incomjyleta Beck., etc. and thèse can only 

 be easily obtained by breeding. 



The female with their corneous and sometimes long ovipositors, 

 place the eggs on those parts of the plants in and upon which the 

 larvae are intended to live; the very variable length and form of 

 the ovipositor dénotes that the adaptations in this way are very 

 numerous and différent. The métamorphoses of many species, 

 especially the harmful ones hâve been studied. 



The habits of the larvae are very variable and thèse may be 

 divided into four distinct groups according to the varions parts of 

 the plants which they attack. 



\st groti.p. 



Larva feeding in fruits, usually preferring succulent fruits 

 and are known as f ruit-maggots ; they attack différent species of 

 plants, digging into the pulp, going to the inner parts of the fruit 

 and usually cause its fall ; thèse belong chiefly to the Dacinae and 

 most Ceratitininae. 



