196 



Studies ix Geology^ No. 3 



Figs. I, 

 3- 

 4- 

 S- 

 6. 



7- 



8, 

 10. 

 II. 

 12. 

 13, 

 15- 

 16. 



17- 

 18, 



M- 



19. 



Plate X. 



Tellina zapotalensis Spieker. 



Tellina (Eurytellina) aequicincta Spieker. 



Tellina (Angulus) pressa Dall, side view X5. 



Tellina (Angulus) singewaldi Spieker. 



Pitaria (Lamelliconcha) planivieta (Guppy). 



Solecurtus (Pharella) planifolliculus Spieker. 



Mulina .zorritensis (Nelson). 



Labiosa (Raeta) gardnerae Spieker. 



Labiosa (Raeta) venlricosa Spieker. 



Corbula (Aloidis) prenuncia Spieker, X3. 



Corbula (Aloidis) bradleyi Nelson. 



Corbula (Cuneocorbula) fabiformis Spieker, X3. 



Corbula (Cuneocorbula) propinqua Spieker. 



Corbula (Cuneocorbula) bravoana Spieker. 



Corbula (Cuneocorbula) acutirostra Spieker. 



