Sèancc du îô Décembre 1915 155 



liave moved S. into and across 

 the «niaiches))of thePalaearclic 

 region or as (/>) species of non- 

 Palaearctic origin Nvhich have 

 invaded Pahiearctic areas. 

 The poverty of this fanna— Egypt has bnl 31 species 

 recorded against tlie 54 which have been taken w ilhin a 

 circle of 6 miles ronnd Beirul — is explained by the 

 extreme barrenness of the deserts vsliich border the 

 narrow cnllivaled ship of Ihe Nile and \'alley (he liiniled 

 Nile Delta and by the extremely close cultivation of tne 

 irrigated area. In the desert only a few forms, the larvae 

 of which feed or can feed on desert plants, occur at all. 

 S.(/I(fncononie, M. var. (leserlicoI(i,Ph'beiiis loewii n.<ji(j<is 

 &. Hesperin ameiiophis do not occur, save as accidental 

 stragglers in cultivation. In the Delta and in the Nile 

 Valle}^ as far as Assuan, the enoiinous {juantilative pre- 

 ponderance of (a) cultivated i)Iants and (h) common 

 weedsofcultivation in the flora and the frecpienl Hooding 

 of large areas coiiibine to restrict the number of species 

 of Rhoj)alocera which can exist there. It is to irrigation 

 that I am inclined to ascril)e the absence — oi- if they do 

 exist in Egypt the extreme rarity of Satijridae whose 

 ground feeding larxae which mostly i)upate below the 

 surface of the soil are with veiy ïvw exceptions intolerant 

 of excessive moisture. The «Stej)i)e» region — for it is not 

 real desert — which extends as a coastal slri[) from Alex- 

 andria to Solium may eventually give us species which 

 have not yet been taken in the desert or in the cullivat(>d 

 area. It caii scarcely be said to have been exj)Iored as 

 yet sa\e in its barrenest pail — the immediate neigh- 

 bourhood of Lake Mareotis Ä Alexandiia but of its tenor 



