Transmission 



29 



collecting them for the purposes of the class in zoology. His finds 

 were both numerous and varied, and it was decided to prospect this 

 collecting ground. It proved to be at his own village, El Marg, 

 some nine miles north of Cairo, just beyond the popular and rapidly 

 extending northern suburb of Cairo on the Zeitun-Mataria line. 

 There was a good half-hourly train service, the village lay alongside 

 the railway line and was an agricultural centre, being surrounded 



Fig. 3. — Children from Marg village collecting water fur domestic use. 



by cotton fields and date palm groves. There was no birket, the 

 only water supply to the surrounding fields was a small tertiary 

 canal which traversed the village and derived its supply from the 

 main Ismailia Canal a few miles distant, not far from its origin 

 from the Nile. The village has a population of less than 

 5,000 and its inhabitants are mainly occupied in cultivating the 

 surrounding land. 



As vv'ill be seen from fig. 1, El Marg is situated in the centre 

 of a cultivated plain, roughly triangular in shape, having as its base 

 the Ismailia fresh water canal which runs north from Cairo, and 



