280 Charles Fennev: 



are still vigorously cutting back, as shown in Fig. 37. Spring 

 Creek, a southern tributary, flows partly along the junction be- 

 tween the tertiaries and the Ordovician; it has a deep narrow 

 valley, already referred to. 



Just within the basin a valley enters from the north, and was 

 carefully examined on account of the possibility of a small capture. 

 The locality is shown in plan in Fig. 30. It will be seen that the 

 last left bank tributary of the Parwan has cut back to the Dog 

 Trap Gully, and only a ridge of soft, white clay separates the two 

 streams. Very little perceptible change has taken place in the past 

 fifty years. In the lower part of the stream some small ravines 

 are cutting back. Capture will no doubt take place at this point 

 in time, since the Parwan tributary has a steeper grade and has 

 no basalt to impede its downward cutting. The Dog Trap Gully 

 is flowing along the side of an old basalt-filled river, and in places 

 basalt still occurs in its bed. An interesting relic of earlier days 

 was found on the ridge at the head of this tributary, where hun- 

 dreds of chipped flakes of flint, chert, quartzite, etc., testified to an 

 old aboriginal camping place. 



An observer standing at the bridge some little distance within 

 the wide Parwan basin, would have difficulty in discovering the 

 outlet of the ^Parwan, as the basin appears to be completely sur- 

 rounded by hills. On tlie right bank of this creek an interesting 

 hill occurs (ref. 56, note 16). This is represented in Fig. 32. The 



ir. 



t \ — 







Fig. 32. — Sketch of rid^e at the right of the point where the Parwan 

 Creek crosses the line of the Rowsley Fault. 



basalt in places is ropy in structnre, and the evidence here taken 

 alone would perhaps suggest that the lava had flowed over a low 

 scarp. This is, however, negatived by other observations, as 

 already pointed out in section VIII. (b). 



Just before leaving this basin the river meanders a good deal 

 through irrigable flats, and then passes out through a narrow gut 



