Egyptian Mollusca 



109 



Specimens were less frequent at Marpj than Vivipara or 

 Cleopatra. Pallary's records are from the neighbourhood of 

 Alexandria, from Asswan and from Suez. 



Fig. 81. — Melania tubcrculata, (x l.|.) 



In the bed of a small channel running from a spring into 

 Lake Timsah between Ismailia and Ferry Post very large num- 

 bers of a small black variety w^ere readily discernible on the sandy 

 bottom. 



Melania tuherculata harbours the developmental stages of a 

 bilharzid icorni believed to attain maturity in some aquatic bird. 



LAMELLIBEANCHIA. 



Cyrenid^. 

 Corbicula consobrina, Cailliaud, 1828. 

 In the mud of all the ponds and canals examined this bivalve 



¥iG. Q2.—Corhicula consobrina. (x 1.) 



occurred in large numbers. On the newly made banks of the 

 tertiary canals, resulting from the annual removal of the nmd from 



