96 POLYPLACOPHORA. 



mediate valves having the lateral areas graniferous ; central areas 

 longitudinally most minutely granose-lirate, line undulating. 

 Marginal ligament broad, corneous, glabrous, brown. Length 9, 

 breadth 4 mill. (Rochebr. in Journ. de Conchyl. 1881, p. 43; and 

 Bull. Soc. Philomath. 1880-'81, p. 118). 



Cape'St. Marie, W. Africa (Paris Museum.) 



ACANTHOPLEURA QUATREFAGEi Rochebr. Shell subelongated, 

 complanate ; pitchy, marbled with brown and whitish spots. Ante- 

 rior valve, anterior part of posterior valve and lateral areas of the 

 intermediate valves obscurely granose. Lateral areas very densely 

 vermiculate. Marginal ligament thick, corneous, black, beset with 

 obtuse, short, whitish and rufescent spikes. Length 26, breadth 12 

 mill. (Rochebr. in Bull. Soc. Philom. 1880-'81, p. 117 ; Journ. de 

 Conch. 1881, p. 44). 



Point of Mammelles ; Joalles ; Rufisque (Rochebrune) ; Table Bay, 

 Cape of Good Hope (Verreaux). Mus. Paris. 



Possibly a Nuttallina 



LEPIDOPLEURUS SERERORUM Rochebr. Shell small, ovate pellu- 

 cid, ashey ; anterior valve and posterior part of the posterior, bicos- 

 tate, ribs thick, concentric ; intermediate valves having the lateral 

 areas thick, transversely sulcate, subpectinated below. Marginal 

 ligament red, scaly, scales very minute. Length 11, breadth 6 mill. 

 (Rochebr. in Bull. Soc. Philom. 1880-'81, p. 118). 



Bank of Ar gain, W. Africa {Mus. Paris.) 



3. South African species. 



ONITHOCHITON ALVEOLATUM Rochebrune. Shell ovate elongate, 

 rotund, gray-greenish, anterior valve, posterior part of posterior valve 

 and lateral areas of the intermediate valves radiately striated, the 

 striae cut across; central areas most minutely reticulate-alveolate. 

 Marginal ligament rather wide, shistaceous. Length 24, breadth 14 

 mill. (Rochebr., Bull. Soc. Philom. de Paris, 1883-1884, p. 32). 



Cape of Good Hope, rare; Paris Museum. 



I suppose this is one of the S. African Ischnochitons. 



ACANTHOPLEURA AFRA Rochebr. Shell ovoid, wide, blackish, 

 umbonate, umbones marked with a wide blue band. Anterior valve, 

 posterior part of the posterior valve and lateral areas of the inter- 

 mediate valves regularly and radially strongly granulated. Central 



