EXPLANATION OF PLATE XIX. 



Fig. 2T,- Rissoa verconiana^ Hedley. 

 ,, 24. Amphithalamus costatus, Hedley. 

 ,, 25. Onoba hassiana, Hedley. 

 Figs. 26, 27. Cerithiopsis dannevigi, Hedley. Shell and 

 enlarged apex. 

 ,, 28, 29. Ceriihiopsis ge)iiculosus, Hedley. Shell and 



enlarged apex. 

 ,, 30, 31, 32, 23- Mcirgi>ieUa fulgurata, Hedley. Colour 

 variety and typical form, immature shell in which 

 the spire whorls appear through a film of callus, and 

 senile stage in which the spire is buried under a pile 

 of callus. 



