62 Annals of the South African Museum. 
The arrangement of Families and Genera is in accordance with 
the latest views of leading authorities on the subject. That of the 
higher orders is a slightly modified adaptation of Paul Pelseneer’s 
classification of the Mollusca in Part V. of Sir E. Ray Lankester’s 
‘Treatise on Zoology.’’ (London, 1906.) 
In the use of Family names, I have followed those writers who 
employ a few only, in a wide sense, rather than a larger and possibly 
unnecessary number of smaller families. 
April, 1912. 
REFERENCE LIST. 
Sus-Kinepou MOLLUSCA, Cuvier, 1795. 
(La Décade Philos. Litt. et Politique, Paris, v. p. 391, as Mollusques.) 
Grape PRORHIPIDOGLOSSOMORPHA, Grobben, 1894. 
(Sitz.-Ber. Akad. Wiss. Wien, p. 86.) 
Cuass GASTROPODA, Cuvier, 1795. 
(Magasin Encycl. ii. p. 448, as Gastéropodes. ) 
Sus-Crass HUTHYNEURA, Spengel, 1881. 
(Zeitschr. f. wissens, Zool. Leipzic, p. 372.) 
OrpeEr PULMONATA, Cuvier, 1817. 
(Régne Anim. ii. pp. 387, 401, as Pulmonés.) 
Sus-Orper STYLOMMATOPHORA, Schmidt, 1855. 
(Abhandl. Naturwiss. vereins. Sachs. Halle, p. 7.) 
TRIBE AGNATHA, Morch, 1859. . 
(Mal. Blitt. vi. p. 109.) 
Faminy APERIDA, Mollendorff, 1903. 
(Conch. Cab. p. 5.) 
Genus APERA, Heynemann, 1885. 
(Jahrb. d. Deutsch. Mal. Ges. xii. p. 20.) 
(= Chlamydephcrus, Binney, 1879, not Chlamydophorus, Harlan, in 
Mammalia 1825.) 
Type of Genus A. gibbonsi (Binn.) 
1. APERA BURNUPI, Smith. 
1892 Apera burnupi, Smith, A.M.N.H. x. p. 466. D. 
1897 ‘sj »  Clige. mao MIN Ei, xx. pedals pl. 7B, 
Te 1-6, A, 
