104 H. C. EFFLATOUN. 



black band on the lower margin is much deeper and occupies the 

 two-thirds of thesegment^, so that the yellow markings on the upper 

 part of the segment are isolated and mnch sinaller. 



Length from 7 to 8| nun. 



Becker in his excellent work on the Egyptian Diptera seems to 

 hâve overlooked two of the most important spécifie characters, 

 which are: — the présence of the vena spuria, and the absence of 

 the tufts of erect bristles on the lamellse of the maie genitalia. 

 This présence or absence of the vena spuria is a very easy and 

 reliable means of distinguishing between our two Egyptian species, 

 a character which liad previously been overlooked by Loew in his 

 original description of S. spinùjera, and pointed ont for the first 

 time by Thomson, and later by Bezzi. Another very reliable 

 and equally important character is the présence or absence of the 

 thick strong spine near the ba&e of the posterior tibise, below ; 

 this character is not empnasised by Becker, probably for the reason 

 that he used the common European ^'. pipiens (which also does not 

 possess the spine), for comparison with his new S. suhtilis. 



This species is not iincommon in Egypt. Ont of a séries of fifty 

 Syritta, only six tiirned ont to be subtilis and the rest s-pinigera, 

 and the six spécimens (two maies and four females) were ail caught 

 in my garden at Shoubrah, in the months of November, December 

 and January. Becker has found it at Luxor and Suez. 



So far this species has only been recorded from Egypt but 

 very probably it exists in other parts of North Africa. 



Wliile this work was in the press I hâve obtained large séries 

 of the above species at Eamleh "(Alexandria) (18.6.22); they were 

 hovering on Polygomwi equisetifoliuni on the edge of a Banana 

 plantation. *S'. s-pinigera was also présent, but the above species 

 greatlv nutnumbered it. 



