2Ö6 lììilìrtiì) de la Société Royale Éntomoiogiquc d'Egypte 



This interesling dimorphic species is abundant 

 in dry torrent beds among the dried remains oi the 

 annual vegetation, in the calcareous desert country 

 E. and S.E: of Jerusalem (\\ adi Kelt, etc.). It does not 

 extend onto the Hat clay plains round Jericho nor on 

 the, higher parts oi' Judaea. Black individuals at all 

 stages are rarer than the others and there were no 

 intermediate forms observed. Specimens of this 

 species have been often found in the webs of the spider 

 Arglope brucnichi, Scop, on the bushes of Atriplex. 



The pale form is extremely like C. iLailcii^: and 

 piesents even an aberration with jiale stripes corrcs- 

 jwriding to ob. manjiiieUus Serv. of that species, but 

 is always recognisable by the lateral pronotal keels 

 obsolete in metazona and, in the male sex, by the 

 structure of the cerei (Lvarov, Journ. Bombay Nat. 

 llisl. Soc, XXVm, i^-ri, p. :U)()). Hind libiae of the 

 pale form are dirty-^'ellowish. 



It is very curious that a species should exist in the 

 desert, buff in one form, nearly black in the other. 

 Buxton has discussed this case in relation to other 

 problems of coloration in desert animals in his recent 

 book (A.nimal Life in Deserts, Chapt. VII; London, 

 1923). 



93. Thisoecetrus littoralis (Charp). 

 Jericho, 11 April. 



94.* Thisoecetrus continuus (Walk.). 



(LIvarov .luitom. Mon. Mag., ."^rd ser., IX, tq^I. 



p. sr.). 



