( 4r,2 ) 



distal extremity of disiiil cell, thence curving across lirst posterior cell a little 

 beyoud its middle and passing into au irregular blotch suffusing submarginal trans- 

 verse vein and jnnction of latter with second longitudinal vein, and terminating at 

 distal extremity of first longirndinal vein, but leaving extreme tip of marginal cell, 

 as also that of interior submarginal cell, unoccupied. The degree of development of 

 the oblique band just described varies in different individuals; sometimes the band 

 is well developed, fairly dark, and so broad as greatly to restrict the extent of 

 the buff-coloured area in the proximal portion of the wing; in other instances the 

 central portion of the band is so faint as to be scarcely distinguishable, so that tlie 

 band is divided into two blotches, one extending from aual cell to base of third 

 posterior cell, the other suffusing the jnnction of the submarginal transverse vein 

 with the second longitudinal ; in all cases the milky hind border makes a deep 

 indentation into the distal portion of the discal cell : first costal c:ell occasionally 

 mummy-brown. Squamae isabella-coloured, fringes whitish. 



Hnltfirex : Stalks bufl' or cream-buff, knobs cream-coloured, sometimes darker 



at base. 



Le(/s : Front femora clove-brown, extreme tips cinnamon-rufous, middle and 

 hind femora cinnamon-rufons, lower portion of their anterior surfaces clove-brown, 

 middle and hind femora sometimes mainly clove-brown, all femora, as also tibiae 

 and tarsi, clothed above with whitish scales, bristles on femora, tibiae, and tarsi 

 black ; tibiae and tarsi cinnamon-rufous, front tibiae sometimes more or less clove- 

 brown, at least on inside, middle and hind tibiae long and slender. 



Algeiuan Sahara : type and three para-types from El Meksa, south of 

 El Golea, -!. iv. 1912; two specimens from the southern portion of the Oned Mya, 

 5. V. 1912 ; two from El Golea, 10-13. v. 1912. 



The author has much pleasure in naming this fine species in honour of Herr 

 Th. Becker, in grateful recognition of the generous assistance afforded by him in the 

 working out of Dr. Hartert's collection. 



In coloration and general ai)pearance Exoprosopa he.ckeri presents a distinct 

 resemblance to E. alhidu Walk, ("i = E. bagdadensis Macq.), the type of wliich is 

 stated by Walker to be from the " East Indies," and to E. olicierii Macq., of which 

 the typical example was obtained in Arabia. In neither of these species, however, 

 are the distal extremity and hind border of the wing distinctly milky, as is the case 

 in E.he<:licri,yi\\\\e tlie latter is further distinguished, inter alia, by its first jwsterior 

 cell being open instead of closed, and by the elongation of its middle and hind 

 tibiae. 



Exoprosopa arenacea Becker. 



{Z,-;inrhr.f. fyxl. IIiJii'- "■ />'/''■, IW- vi. p. l-Ol (1901!).) 



Three ? ? from El Meksa, sonth of El Golea, Algerian Sahara, 2. iv. 1912. 



According to the original description the wings in this species arc '• violet- 

 grey," and " harmonise very well with the colour of the sand." The wings in 

 Dr. Hartert's specimens, however, are dark brown, except the tips, hind borders, 

 and an extension from the latter into the distal portion of the discal cell, all of 

 which are either milky-white (two specimens i or light drab-grey (one specimen): 

 the dark colour is sharply differentiated from the pale portion of the wings, and 

 there is no trace of the sui)ernumerary transverse veins mentioned in Becker's 

 description. It will be seen, then, that from the description of the wings alone 

 it would be impossible to recognise Dr. Hartert's specimens as belonging to 



