Trans. X.Z. Inst., Vol. XLTX. 



Plate III. 



Fig. 



[('. K. Foweraker, photo. 

 1. — Transition terrace, grade 1. with mats of Raoulia tenuicaulis. 



■;. 





Hfl 



f-ml 



[C. E. Foweraker, photo. 



Fig. 2. — Mats of Raoulia tenuicaulis growing over stream-edge of a grade 2 terrace 



which is being undermined. 



Face p. 16.] 



