286 JOURNAL OF CONCHOLOGY, VOL. I4, NO. 9, JANUARY, I915. 



The full catalogue serves to emphasise the extreme rarity of this occurrence 

 amongst marine shells ; out of the 170 recent species listed, only 33 are marine, 

 and it is very curious that 15 of the 33 belong to the genus Margiiiella. 



Only ten fossil mollusca are known to present this phenomenon, one being a 

 Helix ; of the 9 marine species 3 are Mafginella. 



The comparative frequency of sinistral Helix aspersa, H. pomatia and Biucinum 

 undattDii in collections is no doubt due in great part to the fact that these species 

 are so largely gathered for food, but on the other hand, a sinistral Littoiina 

 littorea is extraordinarily rare, though we believe that two or three others exist in 

 English collections, as well as the example which M. Dautzenberg believes to be 

 unique. 



Reference is made incidentally to a paper on the sinistral form of Turbinella 

 pynuii L. , the chank shell of the Hindus, by Mr. J. Hornell, Madras Superin- 

 tendent of Pearl Fisheries. He estimates that some 120 reversed specimens exist 

 in temples in India and Ceylon, where they are considered sacred objects. 



One of our members — Mrs. Longstaff — has lately written a very interesting 

 ipaper on a visit to the Southern Sudan, with a list of the non-marine mollusca 

 collected there, three species being new to science. Mrs. Longstaff ascended the 

 White Nile to Rejaf, which is 1,128 miles from Khartum, and had numerous 

 opportunities of collecting on or near the river banks. She points out that the 

 geographical position of the Nile, draining as it does the region of the Great Lakes 

 into the Mediterranean, causes a commingling of Ethiopian and Palaearctic forms. 

 Another interesting point is the extraordinary range of certain species on the 

 African continent, especially freshwater species. Thus Spatha wahlbergi Krs. 

 occurs from Khartum to the Transvaal, as well as westward into Nigeria, while the 

 terrestrial Btirtoa nilotica Pfr. ranges from the Bahr-el-Gebel to Matabeleland, as 

 well as eastward to the River Juba and westward to Lake Tchad. 



Altogether 34 species of Gastropods and 19 Pelecypods were obtained. 



In the September number (vol. xi. , part iii.), of the Proceedings of the Malaco- 

 logical Society, the Rev. E. W. Bowell completes a series of papers on the 

 " Radulse of British Helicids," with figures, the only species which he has not 

 figured being Helicella gigaxiiVit. and ValloJiia pulchella M\\\\. The omission of 

 the latter was due to the writer's inability " to obtain specimens from shells which 

 belonged without doubt to this species." 



An excellent ^ paper has just appeared on the genital organs of the Danish 

 species of Clausilia, by C. M. Steenberg, with good photographic text-figures and 

 plate. The Danish species are C. plicatula Drap., C. lineolala Held, C. bidentata 

 Strom, C. dubia Drap., C. pumila Zgl., C. biplicata Mont., C. plicata Drap., 

 C. ventricosa Drap., C. latninata Mont., and possibly C. parvula Stud. Balea 

 perversa is also included. AL Steenberg remarks that the grouping of these Clau- 

 silias on conchological grounds has been entirely confirmed by anatomical research. 

 He recognises Clausiliastra, Pirostoina, and Alinda as distinct genera. 



1 Journ. Linn. Soc. (Zoology) vol. 32, p. 233 (May, 1914). 



2 Anatoraie des Clausilies Danoises — L, Les Organes Gdnilaux (Bianco Lunos Bogtrykkeri, 

 Copenhagen), 



