348 PEOF. W. AMALITSKT ON PEKMIAN [Aug. 1 89 5, 



PALiEANODONTA SUBCASTOR, mihi. (PI. XIII. fig. 5.) 



1892. Naiadites subcastor, Amalitsky, Palseontographica, vol. xxxix. p. 191, 

 pi. xxii. figs. 30-33. 



1894. Naiadites subcastor, Netshayeff, ' Die Fauna der permischen Ablagerungen 

 des ostlichen Theiles des europaischen Russlands.' 



The South African shells determined as this species conform fully 

 to the diagnosis of Palceanodonta subcastor, and are especially like 

 the forms found near Gorbatoff, Oka river, on horizon P of the 

 Permian marls and sandstones of the Oka-Volga basin. 



This species occurs on all the horizons of the Permian marls and 

 sandstones of Eastern Russia. 



Dimensions: length 21, breadth 10, depth 8; Russian forms: 

 length 19, breadth 10, depth 6. 



Locality. South Africa : Graaf Reinet. 



EXPLANATION OF THE PLATES. 



Plate XII. 



Fig. 1. Palmomutela rhomboidalis, Sharpe, Graaf Eeinet. 1 a, lateral view ; 1 b, 

 showing striated hinge-margin. Sharpe's original specimen. 



2 a, b. Palmomutela rhomboidalis, Sharpe. Bloemkop. 



3. Palmomutela, sp. Graaf Reinet. The original specimen for Sharpe's 

 description of the hinge of Iridina (?) ovata. 3 a, natural size ; 3 b, 

 enlarged, and showing transversely-striated hinge-margin. 



4 a, 4 b. Palmomutela, cf. Keyserlingi, mihi. Graaf Reinet. 



5. Palaomutela, n. sp., aff. orthodontia, mihi. Diamond mines at Kimberley. 

 5 a, showing the external view ; 5 b, showing badly-preserved hinge- 

 line. 



6 a-f. Palaomutela trigonalis, mihi. Diamond mines at Kimberley. 



7 a-e. Palaomutela, n. sp., an . Golowkinskiana, mihi. Diamond mines at 



Kimberley. 



8. Palmomutela, cf. ovalis, mihi. Graaf Reinet. 



9. Palmomutela, sp. Diamond mines at Kimberley. 



10. Palmomutela semilunulata, mihi. Graaf Reinet. 10 a-d, external view ; 

 10 c', showing the hinge-margin ; 10 d', hinge-margin, natural size ; 

 10#"', enlarged; 10d'", hinge-margin from above. 



Plate XIII. 



Fig. 1. Palmomutela Murchisoni, mihi, var. Bedford. 



2. Palmomutela plana, mihi. Graaf Reinet. 



3. Palmomutela, cf. Imvis, mihi. Graaf Reinet. 



4. Palmomutela, sp. n. Diamond mines at Kimberley. 4 a, b, lateral 



view ; 4 c, from above. 



5. Palmanodonta subcastor, mihi. 5 a, lateral view ; 5 b, hinge-margin. 



Graaf Reinet. 



6. Palmanodonta okensis, mihi. 6 a, b, from Graaf Reinet ; 6 c, from 



Bloemkop. 



Copies of Drawings of Naiadites, Dawson. 



Fig. 7. Naiadites (A?ithracoptera) carbonaria, Dawson (' Acadian Geol.' 2nd ed. 

 p. 204, fig. 42). 



8. Naiadites (Anthracomya) elongata, Dawson (ibid. fig. 43). 



9. Naiadites (Anthracoptera) Imvis, Dawson (ibid. fig. 44). 

 10. Naiadites arenacea, Dawson (ibid. fig. 45). 



