ortmann: south American naiades. 



551 



30. Castalina martensi Von Ihering (1893). 

 Von Ihering, 1893, p. 81, PI. 3, fig. 5; Simpson, 1900, p. 865; 1914, p. 1205. 



Type-locality. — Rio Camaquam, Rio Grande do Sul, Brazil. 



New locality. — Rio Jacuhy, Cachoeira, Rio Grande do Sul, Brazil (J. D. Hase- 

 man coll., Januarj^ 27, 1909). Three complete shells and one right valve. 



Dislrihidion. — Our new locality extends the range of this species northward. 

 The Rio Jacuhy belongs to the Guahyba-system, but both the Guahyba and Cama- 

 quam flow into the Lagoa dos Patos. \\m Ihering says that he did not find this 

 species north of the Rio Camaquam. 



This species has been sufficiently well described by Von Ihering. Our youngest 

 specimen shows well developed beak-sculpture, corresponding to the description. 

 The variations mentioned by Von Ihering in the crenulation of the lateral teeth 

 are also seen in our specimens. 



Measurements. 



The height ranges according to Von Ihering from 70 to 79 pr. ct., and the diam- 

 eter from 45 to 50 pr. ct. The location of the beaks is from 21 to 29 pr. ct. Thus 

 our specimens are comparatively higher and more swollen. As far as concerns the 

 height, this is certainly due to the smaller size of my shells, since a similar change 

 in the proportional height with age has been observed in C. nchringi. 



Anatomy. — Of this species Von Ihering (1891, p. 477) says that in most cases 



(seven out of eight) the branchial opening is closed in front. I do not possess the 



soft parts. 



31. Castalina psammoica (D'Orbigny) (1835). 



Unio psammoica D'Orbigny, 1843, p. 608, PI. 71, figs. 4-7; Sowerby, XVI, 1868, 



PI. 93, fig. 507. 

 Castalina psammoica Von Ihering, 1893, p. 79; Von INIartens, 1894, p. 164; 



Simpson, 1900, p. 866; 1914, p. 1206; Haas, 1916, pp. 9, 47. 



Type-locality. — Rio Parana, Itaty, above Corrientes, Argentina. 



Other Localities. — Province Santa Fe, Argentina (D'Orbigny) (farther down the 

 Parana); Rio Paraguay, near mouth of Rio Apa (\'on Ihering) (in Paraguay, at 

 Brazilian boundary); Paraguay (Von Martens); Rio Uruguay, Salto Oriental, 

 Uruguay (Haas). 



