238 MES. JANE LONGSTAFF ON NON-MARINE 



The shells from Mogran and Ad-Duwem have smooth, convex whorls 

 with occasional vestiges of spiral lines, or of an angle on the upper whorls, 

 or subangularity on the body-whorl. Nearly all the rest are distinctly bi- 

 angular (var. hiangulcda, Kiist.) with intermediate moniliform lines. In 

 several o£ the specimens from Abba Island, Hillet Abbas, Gebel En, Kodok, 

 and Lake Shambe, hairs are attached to the " beads." On a shell from 

 Kodok the hairs are remarkably long, some measuring 1*25 mm. in length. 

 These hairy individuals are like those named by Frauenfeld, V. aipillata, 

 but since they do not diffei* in other respects from V. inncoJor they can 

 hardly be considered more than a variety. The specimens of this species I 

 found in ponds near the Pyramids of Gizeh nearly all show traces more or 

 less defined of moniliform sf)iral lines, but I did not observe hairs on any 

 of them ; of course this might arise from carelessness in cleaning them, for 

 the hairs would be easily rubbed off. 



The largest shell is from Hillet Abbas ; it measures alt. 20'5, diam. 17*5 nnn. 

 Some of the others are nearly as big. 



V. unicolor is reported throughout Egypt and the whole basin of the Nile 

 from the Victoria Nyanza, Albert Nyanza, Lake Dembea, East Africa, Lake 

 Tchad, and Senegal. Also sub-fossil in the Fayum. 



Subgenus Cleopatra, Troscliel. 



(3LE0PATRA BULIMOIDES, Oliv. 



Cyelostoma bulivioides, Olivier, 1804, 1812, ' V03'. Emp. Ottoman,' vol. ii. p. 39, vol. iii. 

 p. 68, Atlas ii. pi. 31. fig. 6. 



This species was taken at intervals along the whole length of the White 

 Nile between the mouth near Mogran and Gondokoro. A certain amount 

 of variation was observed, some having smooth convex whorls and others 

 carinated ones, the spiral angle differed somewhat ; also the colour varied 

 from light horn to almost black, or there were dark stripes on a paler 

 ground. None of these characters are of sufficient note to be deemed worthy 

 of specific significance, but it may be of interest to record the extent of their 

 occurrence at different localities. It will be observed that striped and keeled 

 shells were more numerous than unicolorous smooth ones in comparison with 

 the number taken, higher up the river than at the mouth. 



Near Mogran were found one hundred and seventy-five examples ; twenty- 

 four have keels, but on only one is the keel continued to the body-whorl. 

 Eighteen are striped, the rest unicolorous. The largest consists of six 

 whorls, it measures alt, 16, diam. 10 mm. A more slender form has five and 

 a half whorls which measure, alt. 12, diam. 7 mm. 



Ad-Duwem : six, only one striped. 



